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1.
BMJ Case Rep ; 17(6)2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38914529

RESUMO

We report a case of a boy in his middle childhood who presented with inspiratory stridor and lactic acidosis and was subsequently diagnosed with partial biotinidase deficiency. Fibreoptic laryngoscope showed paradoxical vocal fold mobility.Partial biotidinase deficiency is an inherited disorder in which the body is unable to recycle the vitamin biotin. It may result in clinical consequences and can be easily treated with biotin but need a high index of suspicion to diagnose. The main symptoms include ataxia, seizures, hypotonia, psychomotor retardation, alopecia, skin rash, progressive deafness, optic atrophy and life-threatening episodes of metabolic acidosis. Laryngeal stridor is an uncommon presentation, but it is reversible in case of biotinidase deficiency. Invasive procedure like tracheostomy has not been shown to enhance outcomes.


Assuntos
Deficiência de Biotinidase , Sons Respiratórios , Humanos , Masculino , Sons Respiratórios/etiologia , Deficiência de Biotinidase/complicações , Deficiência de Biotinidase/diagnóstico , Biotina/uso terapêutico , Biotina/administração & dosagem , Laringoscopia , Criança
2.
J Control Release ; 369: 325-334, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38565395

RESUMO

Challenges for glioma treatment with nanomedicines include physio-anatomical barriers (the blood-brain barrier and blood-brain tumor barrier), low drug loading capacity, and limited circulation time. Here, a red blood cell membrane-coated docetaxel drug nanocrystal (pV-RBCm-NC(DTX)), modified with pHA-VAP (pV) for all-stage targeting of glioma, was designed. The NC(DTX) core exhibited a high drug loading capacity but low in vivo stability, and the RBCm coating significantly enhanced the stability and prolonged in vivo circulation. Moreover, the Y-shaped targeting ligand pV was modified by a mild avidin-biotin interaction, which endowed RBCm-NC(DTX) with superior barrier-crossing ability and therapeutic efficacy. The integration of nanocrystal technology, cell membrane coating, and the avidin-biotin insertion method into this active targeting biomimetic formulation represents a promising drug delivery strategy for glioma.


Assuntos
Antineoplásicos , Neoplasias Encefálicas , Docetaxel , Membrana Eritrocítica , Glioma , Nanopartículas , Docetaxel/administração & dosagem , Docetaxel/farmacocinética , Docetaxel/química , Glioma/tratamento farmacológico , Animais , Nanopartículas/química , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacocinética , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Membrana Eritrocítica/efeitos dos fármacos , Membrana Eritrocítica/química , Linhagem Celular Tumoral , Neoplasias Encefálicas/tratamento farmacológico , Masculino , Sistemas de Liberação de Medicamentos , Avidina/administração & dosagem , Avidina/química , Humanos , Biotina/química , Biotina/administração & dosagem , Ratos Sprague-Dawley , Barreira Hematoencefálica/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Nus
3.
Protein Expr Purif ; 192: 106043, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34973460

RESUMO

Antibody-drug conjugates (ADCs) are a major therapeutic tool for the treatment of advanced cancer. Malignant cells in advanced cancer often display multiple genetic mutations and become resistant to monotherapy. Therefore, a therapeutic regimen that simultaneously targets multiple molecules with multiple payloads is desirable. However, the development of ADCs is hampered by issues in biopharmaceutical manufacturing and the complexity of the conjugation process of low-molecular-weight payloads to biologicals. Here, we report antibody mimetic-drug conjugates (AMDCs) developed by exploiting the non-covalent binding property of payloads based on high-affinity binding of mutated streptavidin and modified iminobiotin. Miniprotein antibodies were fused to a low immunogenic streptavidin variant, which was then expressed in Escherichia coli inclusion bodies, solubilized, and refolded into functional tetramers. The AMDC developed against human epidermal growth factor receptor 2 (HER2) effectively killed cultured cancer cells using bis-iminobiotin conjugated to photo-activating silicon phthalocyanine. The HER2-targeting AMDC was also effective in vivo against a mouse KPL-4 xenograft model. This AMDC platform provides rapid, stable, and high-yield therapeutics against multiple targets.


Assuntos
Escherichia coli/metabolismo , Expressão Gênica , Imunoconjugados/genética , Animais , Biotina/administração & dosagem , Biotina/análogos & derivados , Biotina/química , Biotina/genética , Biotina/imunologia , Linhagem Celular Tumoral , Clonagem Molecular , Escherichia coli/genética , Humanos , Imunoconjugados/administração & dosagem , Imunoconjugados/química , Imunoconjugados/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias/tratamento farmacológico , Dobramento de Proteína , Receptor ErbB-2/antagonistas & inibidores , Receptor ErbB-2/genética , Receptor ErbB-2/imunologia , Estreptavidina/administração & dosagem , Estreptavidina/química , Estreptavidina/genética , Estreptavidina/imunologia
4.
Nat Chem Biol ; 17(3): 326-334, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33199915

RESUMO

Secreted polypeptides are a fundamental axis of intercellular and endocrine communication. However, a global understanding of the composition and dynamics of cellular secretomes in intact mammalian organisms has been lacking. Here, we introduce a proximity biotinylation strategy that enables labeling, detection and enrichment of secreted polypeptides in a cell type-selective manner in mice. We generate a proteomic atlas of hepatocyte, myocyte, pericyte and myeloid cell secretomes by direct purification of biotinylated secreted proteins from blood plasma. Our secretome dataset validates known cell type-protein pairs, reveals secreted polypeptides that distinguish between cell types and identifies new cellular sources for classical plasma proteins. Lastly, we uncover a dynamic and previously undescribed nutrient-dependent reprogramming of the hepatocyte secretome characterized by the increased unconventional secretion of the cytosolic enzyme betaine-homocysteine S-methyltransferase (BHMT). This secretome profiling strategy enables dynamic and cell type-specific dissection of the plasma proteome and the secreted polypeptides that mediate intercellular signaling.


Assuntos
Betaína-Homocisteína S-Metiltransferase/genética , Biotina/química , Proteínas Sanguíneas/genética , Hepatócitos/metabolismo , Proteoma/genética , Coloração e Rotulagem/métodos , Animais , Betaína-Homocisteína S-Metiltransferase/metabolismo , Biotina/administração & dosagem , Biotinilação , Proteínas Sanguíneas/metabolismo , Expressão Gênica , Células HEK293 , Hepatócitos/citologia , Humanos , Injeções Intraperitoneais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células Musculares/citologia , Células Musculares/metabolismo , Células Mieloides/citologia , Células Mieloides/metabolismo , Especificidade de Órgãos , Pericitos/citologia , Pericitos/metabolismo , Proteoma/metabolismo , Proteômica/métodos
5.
J Med Chem ; 63(15): 8265-8275, 2020 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-32658479

RESUMO

The water-soluble vitamin biotin is essential for cellular growth, development, and well-being, but its absorption, distribution, metabolism, and excretion are poorly understood. This paper describes the radiolabeling of biotin with the positron emission tomography (PET) radionuclide carbon-11 ([11C]biotin) to enable the quantitative study of biotin trafficking in vivo. We show that intravenously administered [11C]biotin is quickly distributed to the liver, kidneys, retina, heart, and brain in rodents-consistent with the known expression of the biotin transporter-and there is a surprising accumulation in the brown adipose tissue (BAT). Orally administered [11C]biotin was rapidly absorbed in the small intestine and swiftly distributed to the same organs. Preadministration of nonradioactive biotin inhibited organ uptake and increased excretion. [11C]Biotin PET imaging therefore provides a dynamic in vivo map of transporter-mediated biotin trafficking in healthy rodents. This technique will enable the exploration of biotin trafficking in humans and its use as a research tool for diagnostic imaging of obesity/diabetes, bacterial infection, and cancer.


Assuntos
Biotina/farmacocinética , Tomografia por Emissão de Pósitrons , Complexo Vitamínico B/farmacocinética , Animais , Biotina/administração & dosagem , Radioisótopos de Carbono/administração & dosagem , Radioisótopos de Carbono/farmacocinética , Feminino , Masculino , Camundongos Endogâmicos BALB C , Distribuição Tecidual , Complexo Vitamínico B/administração & dosagem
6.
J Mater Chem B ; 8(4): 758-766, 2020 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-31897462

RESUMO

Effective attachment of magnetic nanoparticles to neuronal membranes has far-reaching significance in activating ion channels and treating neurodegenerative diseases. Superparamagnetic iron oxide nanoparticles (SPIONs) synthesized by the polyol pyrolysis method have the advantages of rich surface functional groups, excellent magnetic properties, controllable particle size and water dispersibility. We propose that perfusion of biotin into the targeted brain area should be initially performed because it tends to be adsorbed by cell membranes, followed by injection of streptavidin (SA)-modified SPIONs into the same area of the brain. By means of the strong binding force between SA and biotin, the SPIONs may subsequently adhere to the cell surfaces in the brain area. In this work, fluorescein isothiocyanate-streptavidin (FITC-SA) was modified on the surface of polyethylene imine (PEI)-SPIONs by the EDC-NHS method and stereotaxically injected into the biotin-supplemented substantia nigra of mice. The combination of fluorescence detection with transmission electron microscopy (TEM) confirmed that FITC-SA/PEI-SPIONs adhered to neuronal membranes in the substantia nigra of mice 24 h after injection. The results show that our strategy can promote the attachment of SPIONs to neuronal membranes.


Assuntos
Membrana Celular/química , Nanopartículas Magnéticas de Óxido de Ferro/química , Neurônios/química , Substância Negra/química , Animais , Biotina/administração & dosagem , Biotina/química , Adesão Celular , Fluoresceína-5-Isotiocianato/administração & dosagem , Fluoresceína-5-Isotiocianato/química , Injeções Intraperitoneais , Nanopartículas Magnéticas de Óxido de Ferro/administração & dosagem , Teste de Materiais , Camundongos , Camundongos Transgênicos , Tamanho da Partícula , Estreptavidina/administração & dosagem , Estreptavidina/química , Propriedades de Superfície
8.
G Ital Dermatol Venereol ; 154(5): 557-566, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31638351

RESUMO

One of the most common micronutrient deficiencies with cutaneous findings is the vitamin B, also known as biotin, deficiency. Biotin deficiency may be due to congenital lack of biotinidase, or acquired following some conditions that interfere with its absorption, such as inflammatory bowel disorders, a diet too rich in avidin, magnesium deficiency, smoking habit and treatment with broad-spectrum antibiotics, anticonvulsants and sulfonamides. This review highlights the role of biotin in the most common skin disorders such associated with biotin deficiency and an approach to their treatment. Biotin administration may improve the treatment of hair loss when deficiency is detected on the basis of a careful patient history, clinical examination and the determination of serum biotin levels. The use of biotin is rationale in seborrheic dermatitis as the vitamin intercepts the main metabolic pathways underlying the pathogenesis of the disease. Treatment with biotin could also be useful in comedonal acne characterized by a high rate of seborrhea, and may be helpful for acne treated with topical retinoids, contributing to the control of flaking and irritation. The tolerability of biotin is excellent and there is no risk of hypervitaminosis even in the case of high doses. It is important that administration is controlled by physicians and follows a medical diagnosis and prescription. Correct doses used in dermatological conditions are safe and are not at risk of interference with laboratory tests.


Assuntos
Biotina/administração & dosagem , Deficiência de Biotinidase/patologia , Dermatopatias/patologia , Alopecia/tratamento farmacológico , Biotina/metabolismo , Biotinidase/metabolismo , Deficiência de Biotinidase/tratamento farmacológico , Dermatite Seborreica/tratamento farmacológico , Dermatite Seborreica/patologia , Humanos , Dermatopatias/tratamento farmacológico
9.
J Control Release ; 307: 211-220, 2019 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-31170464

RESUMO

The lymphatics are a target for a range of therapeutic purposes, including cancer therapy and vaccination, and both vesicle size and charge have been considered as factors controlling lymphatic targeting. Within this work, a range of liposomal formulations were investigated to develop a liposomal lymphatic targeting system. Initial screening of formulations considered the effect of charge, with neutral, cationic and anionic liposomes being investigated. Biodistribution studies demonstrated that after intramuscular injection, anionic liposomes offered the most rapid clearance to the draining lymphatics with cationic liposomes forming a depot at the injection site. Anionic liposomes containing phosphatidylserine showed higher clearance to the lymphatics and this may result form preferential uptake by macrophages. In terms of vesicle size, smaller unilamellar vesicles gave high lymphatic targeting and a 10-fold increase in concentration was achieved in dose escalation studies. Given that effective trafficking to the lymphatics was achieved, the next step was to enhance retention of the liposomes within the lymphatics, therefore the liposome formulation was combined with an avidin/biotin complex mechanism. The affinity of avidin for biotin allows biotinylated liposomes to complex in the presence of avidin. By pre-dosing with avidin, the biotin-avidin complex can be exploited to promote longer retention of the liposomes at the draining lymphatics. To load these small, biotinylated liposomes with protein, microfluidics manufacturing was used. Using microfluidics, protein could easily be incorporated in these small (~90nm) biotinylated liposomes. Both liposome and protein retention at the local draining lymph nodes was demonstrated with the liposome-biotin-avidin system. These results demonstrate that microfluidics can be used to prepare protein-loaded liposomes that offer enhanced lymphatic targeting and retention of both the liposomes and entrapped antigen.


Assuntos
Lipossomos , Vasos Linfáticos/metabolismo , Microfluídica/métodos , Animais , Avidina/administração & dosagem , Biotina/administração & dosagem , Biotinilação , Feminino , Humanos , Lipossomos/administração & dosagem , Lipossomos/química , Lipossomos/farmacocinética , Macrófagos/fisiologia , Camundongos Endogâmicos C57BL , Fagocitose , Fosfatidilserinas/administração & dosagem , Células THP-1 , Distribuição Tecidual , Vacinas/administração & dosagem
10.
Nutrients ; 11(4)2019 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-31022908

RESUMO

Patients with biotin deficiency present symptoms that are similar to those in patients with acrodermatitis enteropathica (inherent zinc deficiency). However, the association between biotin and zinc deficiency remains unknown. We have previously shown that epidermal keratinocytes of mice fed zinc-deficient (ZD) diets secreted more adenosine triphosphate (ATP) than those of mice fed zinc-adequate (ZA) diets and that epidermal Langerhans cells are absent in ZD mice. Langerhans cells highly express CD39, which potently hydrolyzes ATP into adenosine monophosphate (AMP). Thus, a lack of Langerhans cells in ZD mice leads to non-hydrolysis of ATP, thereby leading to the development of ATP-mediated irritant contact dermatitis. In this study, we examined if biotin-deficient (BD) mice showed the same underlying mechanisms as those in ZD mice. BD mice showed reduced serum zinc levels, disappearance of epidermal Langerhans cells, and enhanced ATP production in the skin. Consequently, irritant contact dermatitis was significantly enhanced and prolonged in BD mice. In conclusion, the findings of our study showed that biotin deficiency leads to zinc deficiency because of which patients with biotin deficiency show similar symptoms as those with acrodermatitis enteropathica.


Assuntos
Biotina/deficiência , Biotina/farmacologia , Pele/metabolismo , Zinco/metabolismo , Trifosfato de Adenosina/metabolismo , Ração Animal/análise , Animais , Biotina/administração & dosagem , Peso Corporal , Dermatite de Contato/etiologia , Dieta , Feminino , Homeostase , Irritantes , Camundongos , Camundongos Endogâmicos BALB C
11.
Int J Pharm ; 557: 329-341, 2019 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-30599231

RESUMO

In the current study, we employed poly(amidoamine) (PAMAM) dendrimers of generation 4 (G4) to deliver paclitaxel (PTX), a poorly soluble anti-cancer agent precisely to cancer cells via its conjugation on dendrimer surface. Further, G4 PAMAM has been PEGylated (PEG) and tagged with Biotin, an essential micronutrient for cellular functions, receptors of which are overexpressed in certain cancers. The synthesized multifunctional conjugates were characterized by 1H NMR and zeta potential analysis techniques. In addition, the conjugates were evaluated in vitro in cell monolayers and 3D spheroids of biotin receptor over-expressed A549 cell line (human non-small cell lung cancer). G4 PTX PEG-Biotin conjugate penetrated at significantly higher extent in monolayers as well as spheroids as studied by flow cytometry and confocal microscopy by visualizing the cells at varied depth. The G4 PTX PEG-Biotin conjugate demonstrated higher cytotoxicity compared to free PTX and G4 PTX PEG conjugate as assessed by MTT assay in monolayers and Presto Blue assay in detached spheroidal cells. G4 PTX PEG-Biotin demonstrated significant inhibition of growth of tumor spheroids. Therefore, the newly synthesized biotin anchored PTX-conjugated dendrimer system is promising and could be further explored for efficiently delivering PTX to biotin receptor overexpressed cancers.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Biotina/administração & dosagem , Dendrímeros/administração & dosagem , Portadores de Fármacos/administração & dosagem , Paclitaxel/administração & dosagem , Polietilenoglicóis/administração & dosagem , Células A549 , Antineoplásicos Fitogênicos/química , Biotina/química , Sobrevivência Celular/efeitos dos fármacos , Dendrímeros/química , Portadores de Fármacos/química , Humanos , Neoplasias/tratamento farmacológico , Paclitaxel/química , Polietilenoglicóis/química , Esferoides Celulares/efeitos dos fármacos , Células Tumorais Cultivadas
12.
Theranostics ; 8(20): 5662-5675, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30555572

RESUMO

Currently, a large number of anti-tumor drug delivery systems have been widely used in cancer therapy. However, due to the molecular complexity and multidrug resistance of tumors, monotherapies remain suboptimal. Thus, this study aimed to develop a multifunctional theranostic nanoplatform for effective cancer therapy. Methods: Folic acid-modified silver sulfide@mesoporous silica core-shell nanoparticle was first modified with desthiobiotin (db) on the surface, then doxorubicin (DOX) was loaded into pore. Avidin was employed as "gatekeeper" to prevent leakage of DOX via desthiobiotin-avidin interaction. Db-modified survivin antisense oligonucleotide (db-DNA) which could inhibit survivin expression was then grafted on avidin at the outer layer of nanoparticle. DOX release and db-DNA dissociation were simultaneously triggered by overexpressing biotin in cancer cells, then combining PTT from Ag2S QD to inhibit tumor growth. Results: This nanoprobe had satisfactory stability and photothermal conversion efficiency up to 33.86% which was suitable for PTT. Due to the good targeting ability and fluorescent anti-bleaching, its signal still existed at the tumor site after tail vein injection of probe into HeLa tumor-bearing nude mice for 48 h. In vitro and in vivo antitumor experiments both demonstrated that drug, gene and photothermal synergistic therapy significantly enhanced antitumor efficacy with minimal systemic toxicity. Conclusion: Our findings demonstrate that this novel nanoplatform for targeted image-guided treatment of tumor and tactfully integrated chemotherapy, photothermal therapy (PTT) and gene therapy might provide an insight for cancer theranostics.


Assuntos
Tratamento Farmacológico/métodos , Terapia Genética/métodos , Hipertermia Induzida/métodos , Terapia de Alvo Molecular/métodos , Neoplasias/diagnóstico , Neoplasias/terapia , Fototerapia/métodos , Animais , Antineoplásicos/administração & dosagem , Biotina/administração & dosagem , Biotina/análogos & derivados , Terapia Combinada/métodos , Modelos Animais de Doenças , Doxorrubicina/administração & dosagem , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Células HeLa , Humanos , Camundongos Nus , Nanopartículas/administração & dosagem , Nanopartículas/química , Oligonucleotídeos Antissenso/administração & dosagem , Radioterapia Guiada por Imagem/métodos , Nanomedicina Teranóstica/métodos , Resultado do Tratamento
13.
J Agric Food Chem ; 66(22): 5723-5732, 2018 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-29758980

RESUMO

The objective of this study was to evaluate alterations in serum metabolites of transition dairy cows affected by biotin (BIO) and nicotinamide (NAM) supplementation. A total of 40 multiparous Holsteins were paired and assigned randomly within a block to one of the following four treatments: control (T0), 30 mg/day BIO (TB), 45 g/day NAM (TN), and 30 mg/day BIO + 45 g/day NAM (TB+N). Supplemental BIO and NAM were drenched on cows from 14 days before the expected calving date. Gas chromatography time-of-flight/mass spectrometry was used to analyze serum samples collected from eight cows in every groups at 14 days after calving. In comparison to T0, TB, TN, and TB+N had higher serum glucose concentrations, while non-esterified fatty acid in TN and TB+N and triglyceride in TB+N were lower. Adenosine 5'-triphosphate was significantly increased in TB+N. Both TN and TB+N had higher glutathione and lower reactive oxygen species. Moreover, TB significantly increased inosine and guanosine concentrations, decreased ß-alanine, etc. Certain fatty acid concentrations (including linoleic acid, oleic acid, etc.) were significantly decreased in both TN and TB+N. Some amino acid derivatives (spermidine in TN, putrescine and 4-hydroxyphenylethanol in TB+N, and guanidinosuccinic acid in both TN and TB+N) were affected. Correlation network analysis revealed that the metabolites altered by NAM supplementation were more complicated than those by BIO supplementation. These findings showed that both BIO and NAM supplementation enhanced amino acid metabolism and NAM supplementation altered biosynthesis of unsaturated fatty acid metabolism. The improved oxidative status and glutathione metabolism further indicated the effect of NAM on oxidative stress alleviation.


Assuntos
Biotina/sangue , Bovinos/sangue , Suplementos Nutricionais/análise , Niacinamida/sangue , Aminoácidos/sangue , Animais , Biotina/administração & dosagem , Ácidos Graxos Insaturados/sangue , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Glutationa/sangue , Metabolômica , Niacinamida/administração & dosagem , Soro/química
14.
Mol Brain ; 11(1): 22, 2018 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-29650024

RESUMO

The trigemino-thalamic (T-T) and trigemino-parabrachial (T-P) pathways are strongly implicated in the sensory-discriminative and affective/emotional aspects of orofacial pain, respectively. These T-T and T-P projection fibers originate from the spinal trigeminal nucleus (Vsp). We previously determined that many vesicular glutamate transporter (VGLUT1 and/or VGLUT2) mRNA-positive neurons were distributed in the Vsp of the adult rat, and most of these neurons sent their axons to the thalamus or cerebellum. However, whether VGLUT1 or VGLUT2 mRNA-positive projection neurons exist that send their axons to both the thalamus and the parabrachial nucleus (PBN) has not been reported. Thus, in the present study, dual retrograde tract tracing was used in combination with fluorescence in situ hybridization (FISH) for VGLUT1 or VGLUT2 mRNA to identify the existence of VGLUT1 or VGLUT2 mRNA neurons that send collateral projections to both the thalamus and the PBN. Neurons in the Vsp that send collateral projections to both the thalamus and the PBN were mainly VGLUT2 mRNA-positive, with a proportion of 90.3%, 93.0% and 85.4% in the oral (Vo), interpolar (Vi) and caudal (Vc) subnucleus of the Vsp, respectively. Moreover, approximately 34.0% of the collateral projection neurons in the Vc showed Fos immunopositivity after injection of formalin into the lip, and parts of calcitonin gene-related peptide (CGRP)-immunopositive axonal varicosities were in direct contact with the Vc collateral projection neurons. These results indicate that most collateral projection neurons in the Vsp, particularly in the Vc, which express mainly VGLUT2, may relay orofacial nociceptive information directly to the thalamus and PBN via axon collaterals.


Assuntos
Neurônios/metabolismo , Núcleos Parabraquiais/metabolismo , Tálamo/metabolismo , Núcleo Espinal do Trigêmeo/metabolismo , Proteína Vesicular 1 de Transporte de Glutamato/genética , Proteína Vesicular 2 de Transporte de Glutamato/genética , Animais , Axônios/metabolismo , Biotina/administração & dosagem , Biotina/análogos & derivados , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Dendritos/metabolismo , Dextranos/administração & dosagem , Formaldeído , Hibridização in Situ Fluorescente , Injeções Subcutâneas , Lábio , Masculino , Proteínas Proto-Oncogênicas c-fos/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Rodaminas/administração & dosagem , Estilbamidinas/administração & dosagem , Sinapses/metabolismo , Proteína Vesicular 1 de Transporte de Glutamato/metabolismo , Proteína Vesicular 2 de Transporte de Glutamato/metabolismo
15.
Bioorg Med Chem ; 25(21): 5952-5961, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-28988625

RESUMO

Vaccination is a reliable method of prophylaxis and a crucial measure for public health. However, the majority of vaccines cannot be administered orally due to their degradation in the harsh gut environment or inability to cross the GI tract. In this study, we report the first proof-of-concept study of orally producible chemically programmed antibodies via specific conjugation of adaptor ligands to endogenous antibodies, in vivo. Pre-immuniztion with 2,4-dinitrophenyl (DNP), or the reactive hapten, 1,3-diketone (DK), or a novel reactive hapten, vinyl sulfone (VS) in mice, followed by oral administration of adaptor ligands composed of the hapten and biotin to the pre-immunized mice resulted in successful in vivo formation of the biotin-hapten-antibody complexes within 2h. Pharmacokinetic evaluations revealed that apparent serum concentrations of programmed antibodies were up to 144nM and that the serum half-lives reached up to 34.4h. These findings show promise for the future development of orally bioavailable drug-hapten-antibody complexes asa strategy to quickly and easily modulate immune targets for aggressive pathogens as well as cancer.


Assuntos
Anticorpos Monoclonais/imunologia , Biotina/imunologia , Haptenos/imunologia , Cetonas/imunologia , Administração Oral , Animais , Anticorpos Monoclonais/farmacocinética , Reações Antígeno-Anticorpo/efeitos dos fármacos , Biotina/administração & dosagem , Haptenos/administração & dosagem , Cetonas/administração & dosagem , Ligantes , Camundongos , Camundongos Endogâmicos BALB C , Estrutura Molecular
16.
J Control Release ; 264: 102-111, 2017 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-28842313

RESUMO

The blood brain barrier separates the circulating blood from the extracellular fluid in the central nervous system and thus presents an essential obstacle to brain transport of therapeutics. Herein, we report on an effective brain-targeted drug delivery system that combines a robust red blood cell membrane-coated nanoparticle (RBCNP) with a unique neurotoxin-derived targeting moiety. The RBCNPs retain the complex biological functions of natural cell membranes while exhibiting physicochemical properties that are suitable for effective drug delivery. CDX peptide is derived from candoxin and shows high binding affinity with nicotinic acetylcholine receptors (nAChRs) expressed on the surface of brain endothelial cells. Through a facile yet robust approach, we successfully incorporate DCDX peptides onto the surface of RBCNPs without compromising the peptide's brain targeting ability. The resulting DCDX-RBCNPs show promising brain targeting efficiency both in vitro and in vivo. Using a glioma mouse model, we demonstrate that doxorubicin-loaded DCDX-RBCNPs have superior therapeutic efficacy and markedly reduced toxicity as compared to the nontargeted drug formulations. While RBCNPs are used as a model system to evaluate the surface modification approach, the reported method can be readily generalized to various types of cell membrane-derived nanocarriers for broad medical applications.


Assuntos
Sistemas de Liberação de Medicamentos , Membrana Eritrocítica , Ouro/administração & dosagem , Nanopartículas Metálicas/administração & dosagem , Peptídeos/administração & dosagem , Venenos de Serpentes , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Biotina/administração & dosagem , Biotina/química , Encéfalo/metabolismo , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Células Cultivadas , Doxorrubicina/administração & dosagem , Doxorrubicina/química , Doxorrubicina/uso terapêutico , Liberação Controlada de Fármacos , Células Endoteliais/metabolismo , Glioma/tratamento farmacológico , Glioma/metabolismo , Ouro/química , Ouro/farmacocinética , Ouro/uso terapêutico , Humanos , Masculino , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Camundongos Endogâmicos ICR , Camundongos Nus , Peptídeos/química , Peptídeos/farmacocinética , Peptídeos/uso terapêutico , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/química , Ratos Wistar , Receptores Nicotínicos/metabolismo , Estreptavidina/administração & dosagem , Estreptavidina/química
17.
Curr Pharm Des ; 23(28): 4198-4205, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28748755

RESUMO

BACKGROUND: The blood-brain barrier restricts drug penetration to the central nervous system. Targeted nanocarriers are new potential tools to increase the brain entry of drugs. Ligands of endogenous transporters of the blood-brain barrier can be used as targeting vectors for brain delivery of nanoparticles. OBJECTIVE: We tested biotin-labeled solid nanoparticles for the first time and compared to biotinylated glutathione- labeled nanoparticles in brain endothelial cells. METHOD: Neutravidin coated fluorescent polystyrene nanoparticles were derivatized with biotin and biotinylated glutathione. As a human in vitro blood-brain barrier model hCMEC/D3 brain endothelial cells were used. Cell viability by MTT test, uptake and transfer of the nanoparticles across the endothelial monolayers were measured. The uptake of the nanoparticles was visualized by confocal microscopy. RESULTS: The tested nanoparticles caused no change in cell viability. The uptake of biotin- and glutathione-labeled nanoparticles by brain endothelial cells was time-dependent and significantly higher compared to non-labeled nanoparticles. The penetration of the glutathione-labeled nanoparticles across the endothelial monolayer was higher than the biotin-targeted ones. Biotin- and glutathione-targeted nanoparticles were visualized in hCMEC/D3 cells. We verified that hCMEC/D3 express mRNA for sodium-dependent multivitamin transporter (SMVT/SLC5A6) responsible for the blood-brain barrier transport of biotin. CONCLUSION: Biotin as a ligand increased the uptake and the transfer of nanoparticles across brain endothelial cells. Biotinylated glutathione could further increase nanoparticle permeability through endothelial monolayers supporting its use as a brain targeting vector.


Assuntos
Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Sistemas de Liberação de Medicamentos , Animais , Transporte Biológico , Biotina/administração & dosagem , Sobrevivência Celular , Células Endoteliais/metabolismo , Glutationa/administração & dosagem , Humanos , Nanopartículas , Distribuição Tecidual
18.
J Control Release ; 255: 73-80, 2017 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-28363519

RESUMO

Tumor heterogeneity, which describes the genetically and phenotypically distinct subpopulations of tumor cells present within the same tumor or patient, presents a major challenge to targeted delivery of diagnostic and/or therapeutic agents. An ideal targeting strategy should deliver a given nanocarrier to the full diversity of cancer cells, which is difficult to achieve with conventional ligand-conjugated nanoparticles. We evaluated pretargeting (i.e., multistep targeting) as a strategy to facilitate nanoparticle delivery to multiple target cells by measuring the uptake of biotinylated nanoparticles by lymphoma cells with distinct surface antigens pretreated with different bispecific streptavidin-scFv fusion proteins. Fusion proteins targeting CD20 or tumor-associated glycoprotein 72 (TAG-72) mediated the specific in vitro uptake of 100nm biotin-functionalized nanoparticles by Raji and Jurkat lymphoma cells (CD20-positive and TAG-72-positive cells, respectively). Greater uptake was observed for pretargeted nanoparticles with increasing amounts of surface biotin, with 6- to 18-fold higher uptake vs. non-biotinylated nanoparticle and fusion protein controls. Fully biotin-modified particles remained resistant to cultured macrophage cell uptake, although they were still quickly cleared from systemic circulation in vivo (t1/2<1h). For single Raji tumor-bearing mice, pretargeting with CD20-specific FP significantly increased nanoparticle tumor targeting. In mice bearing both Raji and Jurkat tumors, pretargeting with both fusion proteins markedly increased nanoparticle targeting to both tumor types, compared to animals dosed with nanoparticles alone. These in vitro and in vivo observations support further evaluations of pretargeting fusion protein cocktails as a strategy to enhance nanoparticle delivery to a diverse array of molecularly distinct target cells.


Assuntos
Anticorpos Biespecíficos/administração & dosagem , Biotina/administração & dosagem , Nanopartículas/administração & dosagem , Polietilenoglicóis/administração & dosagem , Poliestirenos/administração & dosagem , Proteínas Recombinantes de Fusão/administração & dosagem , Animais , Antígenos CD20/imunologia , Antígenos de Neoplasias/imunologia , Biotina/química , Biotina/farmacocinética , Linhagem Celular Tumoral , Feminino , Glicoproteínas/imunologia , Camundongos Endogâmicos BALB C , Nanopartículas/química , Neoplasias/metabolismo , Fagocitose , Polietilenoglicóis/química , Polietilenoglicóis/farmacocinética , Poliestirenos/química , Poliestirenos/farmacocinética , Distribuição Tecidual
19.
Eur J Pharm Sci ; 102: 275-283, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28323116

RESUMO

In a search for the safe vitamin carrier the PAMAM G3 dendrimer covalently substituted with 9 and 10 molecules of vitamin B7 (biotin) and B6 (pyridoxal), respectively (BC-PAMAM) was investigated. Dendrimer substitution with B-group vitamins significantly alters its biological properties as compared to native form. Observed effects on investigated cell parameters including morphology, adhesion, migration and ATP level were different for normal human fibroblasts (BJ) and squamous cell carcinoma (SCC-15) cell lines. BC-PAMAM revealed significantly less pronounced effects on investigated parameters, particularly at higher concentrations (5-50µM), which is relevant with its lower positive surface charge, as compared with native form. The bioconjugate, up to 50µM concentration, appeared to be a safe vitamin carrier to normal fibroblasts, without significant effect on their adhesion, shape and migration as well as on intracellular ATP level. In SCC-15 cells BC-PAMAM, at low concentrations (0.1-0.5µM), altered the cell shape and increase adhesion, whereas at higher concentrations opposite effects were seen. Measurements of cellular level of ATP showed that higher resistance of cancer cells to toxic effects of native PAMAM dendrimers may be due to higher energy supply of cancer cells.


Assuntos
Biotina/administração & dosagem , Dendrímeros/administração & dosagem , Portadores de Fármacos/administração & dosagem , Piridoxal/administração & dosagem , Trifosfato de Adenosina/metabolismo , Biotina/química , Biotina/farmacologia , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Dendrímeros/química , Dendrímeros/farmacologia , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Humanos , Piridoxal/química , Piridoxal/farmacologia
20.
J Control Release ; 259: 128-135, 2017 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-28279799

RESUMO

Microbubbles (MB) are routinely used as contrast agents for ultrasound (US) imaging. We describe different types of targeted and drug-loaded poly(n-butyl cyanoacrylate) (PBCA) MB, and demonstrate their suitability for multiple biomedical applications, including molecular US imaging and US-mediated drug delivery. Molecular imaging of angiogenic tumor blood vessels and inflamed atherosclerotic endothelium is performed by modifying the surface of PBCA MB with peptides and antibodies recognizing E-selectin and VCAM-1. Stable and inertial cavitation of PBCA MB enables sonoporation and permeabilization of blood vessels in tumors and in the brain, which can be employed for direct and indirect drug delivery. Direct drug delivery is based on US-induced release of (model) drug molecules from the MB shell. Indirect drug delivery refers to US- and MB-mediated enhancement of extravasation and penetration of co-administered drugs and drug delivery systems. These findings are in line with recently reported pioneering proof-of-principle studies showing the usefulness of (phospholipid) MB for molecular US imaging and sonoporation-enhanced drug delivery in patients. They aim to exemplify the potential and the broad applicability of combining MB with US to improve disease diagnosis and therapy.


Assuntos
Sistemas de Liberação de Medicamentos , Embucrilato/administração & dosagem , Microbolhas , Animais , Anticorpos/administração & dosagem , Anticorpos/química , Biotina/administração & dosagem , Biotina/química , Encéfalo/metabolismo , Artérias Carótidas/diagnóstico por imagem , Artérias Carótidas/metabolismo , Linhagem Celular Tumoral , Dextranos/administração & dosagem , Dextranos/química , Selectina E/imunologia , Embucrilato/química , Fluoresceína-5-Isotiocianato/administração & dosagem , Fluoresceína-5-Isotiocianato/análogos & derivados , Fluoresceína-5-Isotiocianato/química , Corantes Fluorescentes/administração & dosagem , Corantes Fluorescentes/química , Humanos , Masculino , Camundongos Nus , Imagem Molecular , Neoplasias/diagnóstico por imagem , Neoplasias/metabolismo , Neoplasias/patologia , Neovascularização Patológica , Rodaminas/administração & dosagem , Rodaminas/química , Estreptavidina/administração & dosagem , Estreptavidina/química , Ondas Ultrassônicas , Ultrassonografia , Molécula 1 de Adesão de Célula Vascular/imunologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/imunologia
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