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1.
Chin J Nat Med ; 17(12): 928-934, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31882048

RESUMO

Two new folate-derived analogues, named uncarophyllofolic acids A (1) and B (2), respectively, were isolated from the Uncaria rhynchophylla hook bearing stem (Gouteng in Chinese). The distinct stereochemical structures of 1 and 2 were determined by spectroscopic data analysis in combination with acidic hydrolysis and Marfey's derivatization, along with comparison of their specific rotation and Cotton effect (CE) data with those of the biogenetically related known derivatives as well as theoretical calculations of electronic circular dichroism (ECD) spectra. A plausible biosynthetic pathway of 1 and 2, associating to folate metabolism and the previously reported orychophragines A-C from Orychophragmus violaceus, is discussed.


Assuntos
Ácido Fólico/química , Extratos Vegetais/química , Uncaria/química , China , Cromatografia Líquida de Alta Pressão , Ácido Fólico/análogos & derivados , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Caules de Planta/química
2.
Analyst ; 144(22): 6729-6735, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31612877

RESUMO

The conjugation of ligands to nanoparticles as drug delivery systems that target specific cells is a promising approach for the delivery of therapeutic agents to tumor cells. Herein, we prepared green-emission fluorescent carbon nanodots (CNDs) by a facile hydrothermal method with d-(+)-glucosamine hydrochloride and l-aspartic acid as the precursors, then covalently conjugated with folate (FA), polyethyleneimine (PEI) and hyaluronic acid (HA) to develop dual ligand-decorated nanocarriers (FA-PEI-HA-CNDs) for the targeted imaging of cancer cells. FA-PEI-HA-CNDs integrated the excellent fluorescence property of CNDs, and can be used for the real-time and noninvasive location tracking of cancer cells. The cellular uptake study demonstrated that FA-PEI-HA-CNDs markedly improved the internalization efficiency in A-549 cells via folate/CD44 receptor-mediated endocytosis in comparison with that of the A549 cells pretreated with excess FA, HA, and FA and HA. Therefore, these dual folate/CD44 receptor-targeted CNDs (FA-PEI-HA-CNDs) show promising potential for cancer detection, drug delivery, and individualized treatment as performance platforms.


Assuntos
Corantes Fluorescentes/química , Pontos Quânticos/química , Células A549 , Carbono/química , Carbono/toxicidade , Endocitose/efeitos dos fármacos , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/toxicidade , Receptores de Folato com Âncoras de GPI/metabolismo , Ácido Fólico/análogos & derivados , Ácido Fólico/síntese química , Ácido Fólico/toxicidade , Humanos , Receptores de Hialuronatos/metabolismo , Ácido Hialurônico/análogos & derivados , Ácido Hialurônico/síntese química , Ácido Hialurônico/toxicidade , Ligantes , Microscopia Confocal/métodos , Microscopia de Fluorescência/métodos , Polietilenoimina/análogos & derivados , Polietilenoimina/síntese química , Polietilenoimina/toxicidade , Pontos Quânticos/toxicidade
3.
Int J Nanomedicine ; 14: 6519-6538, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31616142

RESUMO

Background: Polycation carriers show great foreground in the developing efficient and safe gene delivery; nevertheless, they are cytotoxic and unstable in vivo because of the excess cationic charge. PEGylation improves the biocompatibility and stability of polycation, whereas PEGylation restrains the endosomal escape to some extent. Materials and methods: To address this issue and promote the transfection in vivo, a pH-sensitive conjugate folate-polyethylene glycol-carboxylated chitosan (shorten as FA-PEG-CCTS) was designed and coated on the surface of PEI/NLS/pDNA (PNDs), forming a versatile gene carrier FA-PEG-CCTS/PEI/NLS/pDNA (FPCPNDs). The novel carrier exhibited a few picturesque characteristics, including (i) neutral surface charge to restrain nonspecific interactions; (ii) folate receptors (FR)-mediated endocytosis to augment cellular uptake; (iii) dual proton sponge effect to realize endosome escape, and (iv) nuclear localization sequences (NLS) to enhance the transfection of pDNA. Results: FPCPNDs could compress and protect pDNA from degradation. FPCPNDs energetically targeted tumor cells because of their high binding affinity between FA and highly expressed FR on the tumor surface, accordingly enhancing the cellular uptake. In the acidic endosomes, FA-PEG-CCTS segment dissociated from PNDs. Then, PNDs realized endosomal escape through the proton sponge effect of PEI. Furthermore, FPCPNDs showed admirable transfection efficiency with the aid of NLS peptides. What's more, in vivo studies revealed that FPCPNDs had supreme antitumor activity among the whole preparations. Conclusion: In vitro and in vivo assays thus demonstrate that FPCPNDs is a hopeful strategy for gene delivery.


Assuntos
Endossomos/metabolismo , Neoplasias/metabolismo , Transfecção , Animais , Morte Celular , Linhagem Celular Tumoral , Quitosana/química , DNA/genética , DNA/metabolismo , Endocitose , Feminino , Ácido Fólico/análogos & derivados , Ácido Fólico/química , Terapia Genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Camundongos Endogâmicos BALB C , Neoplasias/patologia , Sinais de Localização Nuclear , Tamanho da Partícula , Plasmídeos/metabolismo , Polietilenoglicóis/química , Polietilenoimina/análogos & derivados , Polietilenoimina/química , Eletricidade Estática
4.
Arch Biochem Biophys ; 674: 108106, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31520592

RESUMO

In view of previous crystallographic studies, N4-hydroxy-dCMP, a slow-binding thymidylate synthase inhibitor apparently caused "uncoupling" of the two thymidylate synthase-catalyzed reactions, including the N5,10-methylenetetrahydrofolate one-carbon group transfer and reduction, suggesting the enzyme's capacity to use tetrahydrofolate as a cofactor reducing the pyrimidine ring C(5) in the absence of the 5-methylene group. Testing the latter interpretation, a possibility was examined of a TS-catalyzed covalent self-modification/self-inactivation with certain pyrimidine deoxynucleotides, including 5-fluoro-dUMP and N4-hydroxy-dCMP, that would be promoted by tetrahydrofolate and accompanied with its parallel oxidation to dihydrofolate. Electrophoretic analysis showed mouse recombinant TS protein to form, in the presence of tetrahydrofolate, a covalently bound, electrophoretically separable 5-fluoro-dUMP-thymidylate synthase complex, similar to that produced in the presence of N5,10-methylenetetrahydrofolate. Further studies of the mouse enzyme binding with 5-fluoro-dUMP/N4-hydroxy-dCMP by TCA precipitation of the complex on filter paper showed it to be tetrahydrofolate-promoted, as well as to depend on both time in the range of minutes and the enzyme molecular activity, indicating thymidylate synthase-catalyzed reaction to be responsible for it. Furthermore, the tetrahydrofolate- and time-dependent, covalent binding by thymidylate synthase of each 5-fluoro-dUMP and N4-hydroxy-dCMP was shown to be accompanied by the enzyme inactivation, as well as spectrophotometrically confirmed dihydrofolate production, the latter demonstrated to depend on the reaction time, thymidylate synthase activity and temperature of the incubation mixture, further documenting its catalytic character.


Assuntos
Fluordesoxiuridilato/metabolismo , Tetra-Hidrofolatos/metabolismo , Timidilato Sintase/metabolismo , Animais , Desoxicitidina Monofosfato/análogos & derivados , Desoxicitidina Monofosfato/metabolismo , Inibidores Enzimáticos/metabolismo , Ácido Fólico/análogos & derivados , Ácido Fólico/metabolismo , Camundongos , Ligação Proteica , Espectrofotometria Ultravioleta
5.
Int J Nanomedicine ; 14: 4309-4317, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31354262

RESUMO

Background: The intraoperative visualization of tumor cells is a powerful modality for surgical treatment of solid tumors. Since the completeness of tumor excision is closely correlated with the survival of patients, probes that can assist in distinguishing tumor cells are highly demanded. Purpose: In the present study, a fluorescent probe JF1 was synthesized for imaging of tumor cells by conjugating a substrate of cathepsin B (quenching moiety) to Oregon Green derivative JF2 using a self-immolative linker. Methods: JF1 was then loaded into the folate-PEG modified CaCO3 nanoparticles. The folate receptor-targeted, pH-dependent, and cathepsin B activable CaCO3 nanoprobe was test in vitro and in vivo for tumor imaging. Results: CaCO3 nanoprobe demonstrated good stability and fast lighting ability in tumors under low pH conditions. It also showed lower fluorescence background than the single cathepsin B dependent fluorescent probe. The pH-dependent and cathepsin B controlled "turn-on" property enables precise and fast indication of tumor in vitro and in vivo. Conclusion: This strategy of controlled drug delivery enables in vivo imaging of tumor nodules with a high signal-to-noise ratio, which has great potential in surgical tumor treatment.


Assuntos
Carbonato de Cálcio/química , Catepsina B/metabolismo , Diagnóstico por Imagem , Nanopartículas/química , Neoplasias/diagnóstico por imagem , Animais , Corantes Fluorescentes/química , Ácido Fólico/análogos & derivados , Ácido Fólico/química , Humanos , Concentração de Íons de Hidrogênio , Células MCF-7 , Camundongos , Nanopartículas/ultraestrutura , Neoplasias/patologia , Especificidade de Órgãos , Polietilenoglicóis/química
6.
Nanomedicine (Lond) ; 14(15): 2011-2025, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31355696

RESUMO

Aim: Constructing a new drug-delivery system using carboxylated graphene quantum dots (cGQDs) for tumor chemotherapy in vivo. Materials & methods: A drug-delivery system was synthesized through a crosslink reaction of cGQDs, NH2-poly(ethylene glycol)-NH2 and folic acid. Results: A drug delivery system of folic acid-poly(ethylene glycol)-cGQDs was successfully constructed with ideal entrapment efficiency (97.5%) and drug-loading capacity (40.1%). Cell image indicated that the nanosystem entered into human cervical cancer cells mainly through macropinocytosis-dependent pathway. In vivo experiments showed the outstanding antitumor ability and low systemic toxicity of this nanodrug-delivery system. Conclusion: The newly developed drug-delivery system provides an important alternative for tumor therapy without causing systemic adverse effects.


Assuntos
Antineoplásicos/administração & dosagem , Portadores de Fármacos/química , Grafite/química , Mitoxantrona/administração & dosagem , Pontos Quânticos/química , Neoplasias do Colo do Útero/tratamento farmacológico , Animais , Antineoplásicos/farmacocinética , Antineoplásicos/uso terapêutico , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Feminino , Ácido Fólico/análogos & derivados , Células HeLa , Humanos , Camundongos Nus , Mitoxantrona/farmacocinética , Mitoxantrona/uso terapêutico , Neoplasias do Colo do Útero/patologia
7.
Acta Crystallogr D Struct Biol ; 75(Pt 7): 682-693, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31282477

RESUMO

Tuberculosis is a disease caused by Mycobacterium tuberculosis and is the leading cause of death from a single infectious pathogen, with a high prevalence in developing countries in Africa and Asia. There still is a need for the development or repurposing of novel therapies to combat this disease owing to the long-term nature of current therapies and because of the number of reported resistant strains. Here, structures of dihydrofolate reductase from M. tuberculosis (MtDHFR), which is a key target of the folate pathway, are reported in complex with four antifolates, pyrimethamine, cycloguanil, diaverdine and pemetrexed, and its substrate dihydrofolate in order to understand their binding modes. The structures of all of these complexes were obtained in the closed-conformation state of the enzyme and a fine structural analysis indicated motion in key regions of the substrate-binding site and different binding modes of the ligands. In addition, the affinities, through Kd measurement, of diaverdine and methotrexate have been determined; MtDHFR has a lower affinity (highest Kd) for diaverdine than pyrimethamine and trimethoprim, and a very high affinity for methotrexate, as expected. The structural comparisons and analysis described in this work provide new information about the plasticity of MtDHFR and the binding effects of different antifolates.


Assuntos
Antagonistas do Ácido Fólico/química , Ácido Fólico/análogos & derivados , Mycobacterium tuberculosis/enzimologia , Tetra-Hidrofolato Desidrogenase/química , Sítios de Ligação , Cristalização/métodos , Cristalografia por Raios X/métodos , Escherichia coli/genética , Ácido Fólico/química , Humanos , Ligantes , Modelos Moleculares , Conformação Proteica , Tuberculose/microbiologia
8.
Int J Mol Sci ; 20(9)2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-31052315

RESUMO

(1) Background: The folate receptor (FR) is a target for cancer treatment and detection. Expression of the FR is restricted in normal cells but overexpressed in many types of tumors. Folate was conjugated with peptides for enhancing binding affinity to the FR. (2) Materials and Methods: For conjugation, folate was coupled with propargyl or dibenzocyclooctyne, and 4-azidophenylalanine was introduced in peptides for "click" reactions. We measured binding kinetics including the rate constants of association (ka) and dissociation (kd) of folate-peptide conjugates with purified FR by biolayer interferometry. After optimization of the conditions for the click reaction, we successfully conjugated folate with designed peptides. (3) Results: The binding affinity, indicated by the equilibrium dissociation constant (KD), of folate toward the FR was enhanced by peptide conjugation. The enhanced FR binding affinity by peptide conjugation is a result of an increase in the number of interaction sites. (4) Conclusion: Such peptide-ligand conjugates will be important in the design of ligands with higher affinity. These high affinity ligands can be useful for targeted drug delivery system.


Assuntos
Receptores de Folato com Âncoras de GPI/metabolismo , Ácido Fólico/análogos & derivados , Alquinos/química , Azidas/química , Química Click/métodos , Ciclo-Octanos/química , Receptores de Folato com Âncoras de GPI/química , Ácido Fólico/metabolismo , Simulação de Acoplamento Molecular , Peptídeos/química , Fenilalanina/análogos & derivados , Fenilalanina/química , Propanóis/química , Ligação Proteica
9.
Int J Mol Sci ; 20(9)2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-31052347

RESUMO

High-risk human papilloma virus (HPV) infection is directly associated with cervical cancer development. Arsenic trioxide (ATO), despite inducing apoptosis in HPV-infected cervical cancer cells in vitro, has been compromised by toxicity and poor pharmacokinetics in clinical trials. Therefore, to improve ATO's therapeutic profile for HPV-related cancers, this study aims to explore the effects of length of ligand spacers of folate-targeted liposomes on the efficiency of ATO delivery to HPV-infected cells. Fluorescent ATO encapsulated liposomes with folic acid (FA) conjugated to two different PEG lengths (2000 Da and 5000 Da) were synthesised, and their cellular uptake was examined for HPV-positive HeLa and KB and HPV-negative HT-3 cells using confocal microscopy, flow cytometry, and spectrophotometer readings. Cellular arsenic quantification and anti-tumour efficacy was evaluated through inductively coupled plasma-mass spectrometry (ICP-MS) and cytotoxicity studies, respectively. Results showed that liposomes with a longer folic acid-polyethylene glycol (FA-PEG) spacer (5000 Da) displayed a higher efficiency in targeting folate receptor (FR) + HPV-infected cells without increasing any inherent cytotoxicity. Targeted liposomally delivered ATO also displayed superior selectivity and efficiency in inducing higher cell apoptosis in HPV-positive cells per unit of arsenic taken up than free ATO, in contrast to HT-3. These findings may hold promise in improving the management of HPV-associated cancers.


Assuntos
Antineoplásicos/toxicidade , Trióxido de Arsênio/toxicidade , Ácido Fólico/análogos & derivados , Lipossomos/química , Neoplasias do Colo do Útero/metabolismo , Apoptose/efeitos dos fármacos , Feminino , Células HeLa , Humanos , Papillomaviridae , Polietilenoglicóis/química , Neoplasias do Colo do Útero/virologia
10.
Int J Mol Sci ; 20(9)2019 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-31052503

RESUMO

Craniofacial bone defect anomalies affect both soft and hard tissues and can be caused by trauma, bone recessions from tumors and cysts, or even from congenital disorders. On this note, cleft/lip palate is the most prevalent congenital craniofacial defect caused by disturbed embryonic development of soft and hard tissues around the oral cavity and face area, resulting in most cases, of severe limitations with chewing, swallowing, and talking as well as problems of insufficient space for teeth, proper breathing, and self-esteem problems as a consequence of facial appearance. Spectacular advances in regenerative medicine have arrived, giving new hope to patients that can benefit from new tissue engineering therapies based on the supportive action of 3D biomaterials together with the synergic action of osteo-inductive molecules and recruited stem cells that can be driven to the process of bone regeneration. However, few studies have focused on the application of tissue engineering to the regeneration of the cleft/lip and only a few have reported significant advances to offer real clinical solutions. This review provides an updated and deep analysis of the studies that have reported on the use of advanced biomaterials and cell therapies for the regeneration of cleft lip and palate regeneration.


Assuntos
Materiais Biocompatíveis/uso terapêutico , Fenda Labial/terapia , Fissura Palatina/terapia , Medicina Regenerativa/métodos , Animais , Fenda Labial/epidemiologia , Fenda Labial/patologia , Fenda Labial/fisiopatologia , Fissura Palatina/epidemiologia , Fissura Palatina/patologia , Fissura Palatina/fisiopatologia , Ácido Fólico/análogos & derivados , Ácido Fólico/uso terapêutico , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/uso terapêutico , Osteogênese/efeitos dos fármacos , Transplante de Células-Tronco/métodos , Engenharia Tecidual/métodos
11.
Artigo em Inglês | MEDLINE | ID: mdl-31103944

RESUMO

Folates are important micronutrients in lentils (Lens culinaris Medik.). In this work, the folate extraction workflow in ascorbate-containing buffer was optimized and validated, and the concentrations of eight folate monoglutamates in cultivated and six wild lentil species, grown under field or greenhouse conditions, were quantified by ultra-performance liquid chromatography and mass spectrometry (UPLC-MS). In general wild lentil species had higher folate concentrations than cultivated genotypes. Lens tomentosus had the highest folate concentration with median values of 439.7 and 360.9 µg/100 g in the field and greenhouse, followed by Lens orientalis with 416.6 and 327.6 µg/100 g, respectively. A significant effect (P < 0.05) of growing conditions was observed in four out of six wild lentil species, with seeds from the field having higher folate concentration (6% to 45%) compared with the greenhouse. MeFox, an oxidation product of 5-methyltetrahydrofolate, was present in all lentil species at concentrations 2.2 to 5.6 times higher than the total folates.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Ácido Fólico/análogos & derivados , Ácido Fólico/análise , Glutamatos/isolamento & purificação , Lens (Planta)/química , Espectrometria de Massas/métodos , Ácido Fólico/química , Ácido Fólico/isolamento & purificação , Glutamatos/química , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes , Sementes/química
12.
Muscle Nerve ; 60(2): 124-136, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31074875

RESUMO

Complementary and alternative treatment modalities are commonly utilized by patients for neuropathy and neuropathic pain due to perceived lack of benefit from conventional medical treatment. As the association between metabolic syndrome and neuropathy is increasingly recognized, diet and lifestyle interventions are becoming important components in the management of neuropathy. Progress in the understanding of the gut-immune interaction highlights the role the gut microbiome and inflammation plays in the modulation of neuropathy and neuropathic pain. Evidence for nutritional interventions, exercise, supplements, acupuncture, and mindfulness-based practices in the treatment of neuropathic pain is encouraging. This article reviews the available evidence to support the safe use of complementary and alternative treatments for commonly encountered conditions associated with neuropathy and neuropathic pain. Muscle Nerve 60: 124-136, 2019.


Assuntos
Dietoterapia , Suplementos Nutricionais , Terapia por Exercício , Estilo de Vida , Neuralgia/terapia , Doenças do Sistema Nervoso Periférico/terapia , Complexo Vitamínico B/uso terapêutico , Acetilcarnitina/uso terapêutico , Anti-Inflamatórios não Esteroides/uso terapêutico , Curcumina/uso terapêutico , Dieta , Disbiose/metabolismo , Exercício Físico , Ácidos Graxos Ômega-3/uso terapêutico , Ácido Fólico/análogos & derivados , Ácido Fólico/uso terapêutico , Microbioma Gastrointestinal , Humanos , Medicina Integrativa , Síndrome Metabólica/metabolismo , Neuralgia/metabolismo , Doenças do Sistema Nervoso Periférico/metabolismo , Fosfato de Piridoxal/uso terapêutico , Ácido Tióctico/uso terapêutico , Vitamina B 12/análogos & derivados , Vitamina B 12/uso terapêutico , Complexo Vitamínico B/metabolismo , Deficiência de Vitaminas do Complexo B , Vitamina D/uso terapêutico
13.
Mater Sci Eng C Mater Biol Appl ; 101: 464-471, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31029341

RESUMO

Curcumin shows a potential anticancer activity, as it is involved in signaling pathway suppressing ß-catenin response transcription. In this study, the effects of curcumin released from the biocompatible and biodegradable polyaspartamide based micelles on colon cancer treatment via the Wnt/ß-catenin signaling pathway are investigated. Hydrophobic octadecylamine (C18) and hydrophilic O-(2-aminoethyl) polyethylene glycol (PEG) were grafted on a polysuccinimide (PSI) backbone for micelle formation. Folic acid (FA) was employed to facilitate the targeting activity to colon cancer cells and curcumin was conjugated via acid cleavable linkage, hydrazone (Hyd) to provide the pH sensitive drug release. Two types of micellar structures, Folate-PEG/Hyd-Curcumin/C18-g-PSI (FA-Cur) and PEG/Hyd-Curcumin/C18-g-PSI (NFA-Cur), were synthesized and their chemical structure was identified by 1H NMR spectroscopy. The cytotoxicity carried out by MTT assay informed that the cell viability of FA-Cur treated SW480 was much lower than that of NFA-Cur treated one at the concentration > 0.25 µg mL-1. Western blot assay showed that FA-Cur inhibited the target genes, cyclin D1 and c-myc, more strongly than NFA-Cur at the concentration > 0.5 µg mL-1. From these results, FA-Cur micelles are expected to be a promising candidate for colon anti-cancer via inhibiting Wnt/ß-catenin pathway.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Neoplasias do Colo/metabolismo , Curcumina/química , Curcumina/farmacologia , Ácido Fólico/análogos & derivados , Micelas , Polietilenoglicóis/química , Via de Sinalização Wnt/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Ácido Fólico/química , Humanos
14.
Org Biomol Chem ; 17(27): 6585-6594, 2019 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-31032834

RESUMO

Despite the advantages of photodynamic therapy (PDT) over chemotherapy or radiotherapy such as low side effects, lack of treatment resistance and spatial selectivity inherent to light activation of the drug, several limitations especially related to the photosensitiser (PS) prevent PDT from becoming widespread in oncology. Herein, new folic acid- and biotin-conjugated PSs for tumour-targeting PDT are reported, with promising properties related to PDT such as intense absorption following one-photon excitation in the red or two-photon excitation in the near-infrared, and also high singlet oxygen quantum yield (close to 70% in DMSO). Cellular studies demonstrated that both targeted PSs induced phototoxicity, the folate-targeted PS being the most effective one with 80% of cell death following 30 min of irradiation and a phototoxicity four times higher than that of the non-targeted PS. This result is in accordance with the uptake of the folate-targeted PS in HeLa cells, mediated by the folate receptors. Moreover, this folate-targeted PS was also phototoxic following two-photon excitation at 920 nm, opening new perspectives for highly selective PDT treatment of small and deep tumours.


Assuntos
Biotina/análogos & derivados , Ácido Fólico/análogos & derivados , Neoplasias/tratamento farmacológico , Porfirinas/química , Morte Celular/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Ácido Fólico/farmacologia , Células HeLa , Humanos , Fotoquimioterapia , Fótons , Fármacos Fotossensibilizantes , Porfirinas/farmacologia
15.
J Chromatogr A ; 1594: 34-44, 2019 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-30799066

RESUMO

A rapid, sensitive and reproducible method for analysis of naturally-occurring folates and folic acid in food has been developed and validated. A single-enzyme extraction step, in which a pure recombinant enzyme of plant origin (Arabidopsis thaliana) was used, enabled fast and reproducible deglutamylation during folate extraction within the incubation time of 1 h. Six commonly occurring folate forms (tetrahydrofolate, 5,10-methenyltetrahydrofolate, 10-formylfolic acid, 5-formyltetrahydrofolate, folic acid and 5-methyltetrahydrofolate) were detected and quantified in 9 min using liquid chromatography-tandem mass spectrometry (LC-MS/MS). 13C5-labeled 5-formyltetrahydrofolate, 13C5-labeled folic acid and 13C5-labeled 5-methyltetrahydrofolate were used as internal standards for the quantification. The method is described by a calibration curve (R2>0.99 and trueness 85-115%), a limit of quantification at 0.1 µg/100 g, trueness at 80-120% in spiked samples and certified reference materials, and a precision <10%. However, the precision in quantification of tetrahydrofolate was not within the acceptable limits due to the lack of use of the corresponding internal standard. An interconversion study of unstable formyl forms was performed which showed that 50% of 5,10-methenyltetrahydrofolate is converted to 5-formyltetrahydrofolate during the analysis. The developed LC-MS/MS method is a candidate for a future standard method for folate analysis in food.


Assuntos
Cromatografia Líquida , Ácido Fólico/análise , Análise de Alimentos/métodos , Proteínas de Plantas/metabolismo , Espectrometria de Massas em Tandem , Calibragem , Ácido Fólico/análogos & derivados , Limite de Detecção , Tetra-Hidrofolatos/análise
16.
Drug Dev Ind Pharm ; 45(5): 852-860, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30724621

RESUMO

Chrysin (CH), a phytoconstituent has numerous pharmacological activities including anticancer activity. However, CH suffers from a drawback of poor aqueous solubility and in turn poor bioavailability limiting its clinical utility. In this work CH loaded folate-conjugated pluronic PF127-pluronic F68 mixed micelles were prepared with an objective to augment oral bioavailability and cytotoxicity of CH in human breast cancer cell line MCF-7 by active targeting mechanism. Folate-conjugated PF127 was synthesized and used for preparation of CH-MM. Optimized batch (using factorial design) of CH-MM was characterized by Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), atomic force microscopy (AFM), in vitro CH release, in vivo study, and in vitro cell line study. FTIR study suggested encapsulation of CH into the micelle core. CH-MM showed controlled release of CH releasing higher amount (2.5 fold) in 24 h when compared to CH alone (A-CH). Further significant increase in Cmax (2 fold) and AUC0-∞ (3 fold) for CH-MM when compared to A-CH suggested significant improvement in oral bioavailability of CH. Additionally, CH-MM showed 5 fold reduction in GI50 value of CH when tested in MCF-7 cells reducing GI50 value of CH significantly. CH-MM can serve as a platform carrier system for active targeting of BCS class II molecules with potential anticancer activity.


Assuntos
Antineoplásicos/administração & dosagem , Portadores de Fármacos/química , Flavonoides/administração & dosagem , Administração Oral , Animais , Antineoplásicos/farmacocinética , Disponibilidade Biológica , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Preparações de Ação Retardada , Composição de Medicamentos/métodos , Ensaios de Seleção de Medicamentos Antitumorais , Excipientes/química , Feminino , Flavonoides/farmacocinética , Ácido Fólico/análogos & derivados , Ácido Fólico/química , Humanos , Células MCF-7 , Micelas , Poloxâmero/química , Polietilenoimina/análogos & derivados , Polietilenoimina/química , Ratos , Ratos Wistar
17.
Toxicol Appl Pharmacol ; 368: 49-54, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30794826

RESUMO

INTRODUCTION: Nonalcoholic steatohepatitis (NASH) afflicts 20-36% of individuals with nonalcoholic fatty liver disease (NAFLD). A lipotoxic hepatic environment, altered innate immune signaling and inflammation are defining features of progression to NASH. Activated resident liver macrophages express folate receptor beta (FR-ß) which may be an indicator of progression from steatosis to NASH. The goals of this study were to characterize FR-ß protein expression in human NAFLD and rodent models of NASH, and demonstrate liver targeting of an FR-ß imaging agent to the liver of a rodent NASH model using FR-ß. METHODS: Rat liver lysates from methionine choline deficient (MCD) fed rats, high fat diet (HFD) and methionine choline sufficient (MC+) rat controls were analyzed for hepatic FR-ß protein. The FR-ß-targeted agent, Etarfolatide was injected into MCD and MC + -fed C57BL/6 mice for efficient FastSPECT hepatic imaging. Additionally, FR-ß expression across the stages of human NAFLD from normal to NASH was assessed. RESULTS: FastSPECT images show targeting of Etarfolatide to the liver of mice fed 8 weeks of MCD diet but not control-fed mice. The MCD rat model exhibited significantly increased protein expression of hepatic FR-ß in contrast to HFD or normal samples. Similarly human liver samples categorized as NASH Fatty or NASH Not Fatty showed elevated FR-ß protein when compared to normal liver. FR-ß transcript expression levels were elevated across both NASH Fatty and NASH Not Fatty samples. CONCLUSION: The findings in this study indicate that FR-ß expression in NASH may be harnessed to target agents directly to the liver.


Assuntos
Receptor 2 de Folato/metabolismo , Fígado/diagnóstico por imagem , Fígado/metabolismo , Macrófagos/metabolismo , Imagem Molecular/métodos , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Hepatopatia Gordurosa não Alcoólica/metabolismo , Tomografia Computadorizada de Emissão de Fóton Único , Animais , Biomarcadores/metabolismo , Deficiência de Colina/complicações , Dieta Hiperlipídica , Modelos Animais de Doenças , Receptor 2 de Folato/genética , Ácido Fólico/administração & dosagem , Ácido Fólico/análogos & derivados , Humanos , Masculino , Metionina/deficiência , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/genética , Compostos de Organotecnécio/administração & dosagem , Valor Preditivo dos Testes , Compostos Radiofarmacêuticos/administração & dosagem , Ratos Sprague-Dawley
18.
J Colloid Interface Sci ; 540: 66-77, 2019 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-30634060

RESUMO

Multifunctional nanoparticles (NPs) with high blood-stability, tumor-targeting ability, and stimuli-bioresponsive drug release behaviors are urgently demanded. Herein, folic acid (FA) and galactose (GAL) functionalized, core-crosslinked NPs (CC NPs) with dual-targeting and pH/redox-bioresponsive properties were developed based on amphiphilic FA-poly(6-O-methacryloyl-d-galactopyranose)-b-poly[2-(diisopropylamino) ethyl methacrylate-co-pyridyl disulfide methylacrylate] [FA-PMAgGP-b-P(DPA-co-PDEMA), termed as FA-PMgDP] block copolymers, and then investigated for facilitated hepatoma-targeting delivery of doxorubicin (DOX). A series of PMgDP copolymers were synthesized though two-step RAFT copolymerization followed by acid-induced acetal deprotection reaction. Their well-defined chemical structures and compositions were characterized by 1H NMR and gel permeation chromatography. Nano-sized, non-crosslinked PMgDP NPs (PMgDP NC NPs) with sizes of less than 25 nm in aqueous solution were self-assembled via the solvent exchange method, and PMgDP CC NPs were readily prepared in the presence of dithiothreitol. The drug-loading content of PMgDP CC NPs was up to 15.8% and its entrapment efficiency was 89.0%. In normal physiological conditions, 11.6% of DOX was released from DOX-loaded PMgDP CC NPs at 25 h, whereas in analogous intracellular microenvironment, 95.5% was released at 11 h owing to the acid-induced protonation of tertiary amine and reductive cleavage of disulfide bond in the hydrophobic core. In a cellular uptake study, FA and GAL-mediated, active, dual-targeted DOX-loaded FA-PMgDP CC NPs showed a 3.54-fold increase in cellular uptake efficiency to HepG2 cells compared to that of shown by single GAL-targeted, DOX-loaded PMgDP NC NPs. Results of in vitro cytotoxicity study showed that blank FA-PMgDP CC NPs exhibited good biocompatibility, whereas dual-targeting DOX-loaded FA-PMgDP CC NPs increased cell apoptosis. Therefore, the above results indicated that the well-constructed FA-PMgDP CC NPs with multi-synergistic effect may serve as new nanocarriers in the field of precise hepatoma-targeting drug delivery.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Preparações de Ação Retardada/química , Doxorrubicina/administração & dosagem , Ácido Fólico/análogos & derivados , Galactose/análogos & derivados , Nanopartículas/química , Antibióticos Antineoplásicos/farmacocinética , Antibióticos Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Doxorrubicina/farmacocinética , Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Células Hep G2 , Humanos , Concentração de Íons de Hidrogênio , Neoplasias/tratamento farmacológico , Oxirredução , Polímeros/química
19.
J Mass Spectrom ; 54(4): 316-327, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30675959

RESUMO

Folic acid (FA) plays a vital role in central metabolism, including the one carbon cycle, nucleotide, and amino acid biosynthesis. The development of sensitive, accurate analytical methods to measure FA intermediates in tissues is critical to understand their biological roles in diverse physiological and pathological contexts. Here, we developed a highly sensitive method for the simultaneous quantification of FA intermediates in the nematode Caenorhabditis elegans as a model to dissect metabolic networks. The method was further validated by analyzing the worm folate pool upon RNAi knockdown of the dihydrofolate reductase gene dhfr-1. Comparative mass spectrometry behavior of the FA analogs using two different ion sources, electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI), revealed ESI-MS/MS to be more sensitive, but APCI-MS provided more detailed structure inferences, which can elucidate chemical investigation and synthesis of FA analogs. Finally, we report on the use of in vitro oxidation coupled with high-resolution mass spectrometry as a tool to discover new endogenous FA derivatives in the nematode.


Assuntos
Caenorhabditis elegans/química , Misturas Complexas/análise , Ácido Fólico/análogos & derivados , Ácido Fólico/análise , Animais , Cromatografia Líquida de Alta Pressão/métodos , Ácido Fólico/metabolismo , Espectrometria de Massas/métodos , Redes e Vias Metabólicas , Sensibilidade e Especificidade , Tetra-Hidrofolato Desidrogenase/genética
20.
Pharm Dev Technol ; 24(2): 253-261, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29688120

RESUMO

The key for better antitumor efficacy is to improve the specificity of antitumor drugs for tumor cells and diminish their cytotoxicity to normal tissues. Targeted nanoparticles as antitumor drug delivery system can resolve this problem. In this study, we prepared folate and TAT (arginine-rich cell-penetrating peptide) modified N-PEG-N'-octyl-chitosan to form the folate/TAT-PEG-OC micelles. Then, the molecular structure, morphology, size distribution and bio-safety of the micelles were characterized. In order to investigate the drug-loading capacity of folate/TAT-PEG-OC micelles, doxorubicin (DOX) was used as model drug to prepare DOX-loaded chitosan micelles. Here, the confocal microscopy was used to evaluate the cellular uptake of DOX/folate/TAT-PEG-OC micelles, while the self-built NIR imaging system was used to evaluate the dynamic behavior of ICG-Der-01/folate/TAT-PEG-OC micelles in vivo. Our results demonstrate that the dual-modified PEG-OC micelles not only have good morphology, uniform size distribution and excellent drug loading capacity, but also show a strong capability for the efficient intracellular uptake and enhanced targeting behaviors in a folate receptor positive tumor model (Bel-7402 human hepatocellular cells). All these results suggest the potential application of folate/TAT-PEG-OC micelles in the targeted diagnosis and therapy to different kinds of folate receptor positive tumors.


Assuntos
Arginina/química , Peptídeos Penetradores de Células/química , Quitosana/química , Doxorrubicina/química , Ácido Fólico/química , Animais , Linhagem Celular Tumoral , Doxorrubicina/administração & dosagem , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Ácido Fólico/análogos & derivados , Humanos , Camundongos , Camundongos Nus , Micelas , Polietilenoglicóis/química , Polímeros/química , Ensaios Antitumorais Modelo de Xenoenxerto
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