RESUMEN
We show distinct CH-π interactions and assembly pathways for the amphiphile N-(fluorenylmethoxycarbonyl)-galactosamine and its epimer N-(fluorenylmethoxycarbonyl)-glucosamine. These differences result in the formation of supramolecular nanofibrous systems with opposite chirality. Our results showcase the importance of the carbohydrates structural diversity for their specific biointeractions and the opportunity that their ample interactome offers for synthesis of versatile and tunable supramolecular (bio) materials.
Asunto(s)
Tensoactivos , Estereoisomerismo , Tensoactivos/química , Tensoactivos/síntesis química , Carbohidratos/química , Galactosamina/química , Glucosamina/química , Glucosamina/análogos & derivados , Sustancias Macromoleculares/química , Sustancias Macromoleculares/síntesis química , Nanofibras/químicaRESUMEN
Biologics, including proteins and antisense oligonucleotides (ASOs), face significant challenges when it comes to achieving intracellular delivery within specific organs or cells through systemic administrations. In this study, we present a novel approach for delivering proteins and ASOs to liver cells, both in vitro and in vivo, using conjugates that tether N-acetylated galactosamine (GalNAc)-functionalized, cell-penetrating polydisulfides (PDSs). The method involves the thiol-bearing cargo-mediated ring-opening polymerization of GalNAc-functionalized lipoamide monomers through the so-called aggregation-induced polymerization, leading to the formation of site-specific protein/ASO-PDS conjugates with narrow dispersity. The hepatocyte-selective intracellular delivery of the conjugates arises from a combination of factors, including first GalNAc binding with ASGPR receptors on liver cells, leading to cell immobilization, and the subsequent thiol-disulfide exchange occurring on the cell surface, promoting internalization. Our findings emphasize the critical role of the close proximity of the PDS backbone to the cell surface, as it governs the success of thiol-disulfide exchange and, consequently, cell penetration. These conjugates hold tremendous potential in overcoming the various biological barriers encountered during systemic and cell-specific delivery of biomacromolecular cargos, opening up new avenues for the diagnosis and treatment of a range of liver-targeting diseases.
Asunto(s)
Productos Biológicos , Galactosamina , Galactosamina/química , Hepatocitos/metabolismo , Oligonucleótidos Antisentido/química , Disulfuros/metabolismo , Compuestos de Sulfhidrilo/metabolismo , Productos Biológicos/metabolismoRESUMEN
Off-target toxicity is one of the main challenges faced by anticancer chemotherapeutics. For tumor targeted and precision chemotherapy, we take the advantages of the ligand directed tumor active targeting of small molecule drug conjugates (SMDCs) and the passive tumor targeting of nanoparticles via the enhanced penetration and retention (EPR) effects, put forward a branched small molecule drug conjugate (BSMDC) nanomedicine design concept. In a proof of concept, we used pentaerythritol as the branched moiety, galactosamine (GalN) as the hepatocellular carcinoma (HCC) directing ligands, PTX as a payload, and a stearoyl moiety as the amphiphilic property adjusting group, designed and synthesized BSMDC 1 and prepared its NPs. In cellular level, the BSMDC 1 NPs targeted asialoglycoprotein receptor (ASGPR)-overexpressing HepG2 cells, were effectively taken up in the cells and released in tumor microenvironments, inhibited the HepG2 cell proliferation, arrested HepG2 cell in G2/M phase and induced tumor cell apoptosis. In HepG2 xenograft nude mice, the BSMDC 1 NPs were high specific to target the tumor and demonstrated a higher antitumor efficiency than BSMDC 1, having no apparent influences on mice body weights and major organs, supporting our BSMDC nanomedicine design concept. Therefore, this new strategy may find applications for cancer targeted and precision chemotherapy.
Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Carcinoma Hepatocelular/tratamiento farmacológico , Galactosamina/farmacología , Neoplasias Hepáticas/tratamiento farmacológico , Paclitaxel/farmacología , Bibliotecas de Moléculas Pequeñas/farmacología , Animales , Antineoplásicos Fitogénicos/química , Apoptosis/efectos de los fármacos , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Puntos de Control del Ciclo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Galactosamina/química , Células Hep G2 , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Neoplasias Hepáticas Experimentales/tratamiento farmacológico , Neoplasias Hepáticas Experimentales/metabolismo , Neoplasias Hepáticas Experimentales/patología , Ratones , Ratones Desnudos , Estructura Molecular , Nanomedicina , Paclitaxel/química , Bibliotecas de Moléculas Pequeñas/química , Relación Estructura-ActividadRESUMEN
Nanoparticles (NPs) embedded with bioactive ligands such as carbohydrates, peptides, and nucleic acid have emerged as a potential tool to target biological processes. Traditional inâ vitro assays performed under statistic conditions may result in non-specific outcome sometimes, mainly because of the sedimentation and self-assembly nature of NPs. Inverted cell-culture assay allows for flexible and accurate detection of the receptor-mediated uptake and cytotoxicity of NPs. By combining this technique with glyco-gold nanoparticles, cellular internalization and cytotoxicity were investigated. Regioselective glycosylation patterns and shapes of the NPs could tune the receptors' binding affinity, resulting in precise cellular uptake of gold nanoparticles (AuNPs). Two cell lines HepG2 and HeLa were probed with galactosamine-embedded fluorescent AuNPs, revealing significant differences in cytotoxicity and uptake mechanism in upright and invert inâ vitro cell-culture assay, high-specificity toward uptake, and allowing for a rapid screening and optimization technique.
Asunto(s)
Antineoplásicos/farmacología , Técnicas de Cultivo de Célula , Galactosamina/farmacología , Oro/farmacología , Nanopartículas/química , Antineoplásicos/química , Proliferación Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Galactosamina/química , Oro/química , Células HeLa , Células Hep G2 , Humanos , Estructura Molecular , Tamaño de la Partícula , Células Tumorales CultivadasRESUMEN
Targeting nanoparticles as drug delivery platforms is crucial to facilitate their cellular entry. Docking of nanoparticles by targeting ligands on cell membranes is the first step for the initiation of cellular uptake. As a model system, we studied brain microvascular endothelial cells, which form the anatomical basis of the blood-brain barrier, and the tripeptide glutathione, one of the most effective targeting ligands of nanoparticles to cross the blood-brain barrier. To investigate this initial docking step between glutathione and the membrane of living brain endothelial cells, we applied our recently developed innovative optical method. We present a microtool, with a task-specific geometry used as a probe, actuated by multifocus optical tweezers to characterize the adhesion probability and strength of glutathione-coated surfaces to the cell membrane of endothelial cells. The binding probability of the glutathione-coated surface and the adhesion force between the microtool and cell membrane was measured in a novel arrangement: cells were cultured on a vertical polymer wall and the mechanical forces were generated laterally and at the same time, perpendicularly to the plasma membrane. The adhesion force values were also determined with more conventional atomic force microscopy (AFM) measurements using functionalized colloidal probes. The optical trapping-based method was found to be suitable to measure very low adhesion forces (≤ 20 pN) without a high level of noise, which is characteristic for AFM measurements in this range. The holographic optical tweezers-directed functionalized microtools may help characterize the adhesion step of nanoparticles initiating transcytosis and select ligands to target nanoparticles.
Asunto(s)
Membrana Celular/metabolismo , Células Endoteliales/metabolismo , Glutatión/metabolismo , Nanopartículas/metabolismo , Pinzas Ópticas , Fenómenos Biofísicos , Barrera Hematoencefálica/metabolismo , Encéfalo , Adhesión Celular , Membrana Celular/ultraestructura , Células Endoteliales/citología , Galactosamina/química , Humanos , Ligandos , Microscopía de Fuerza Atómica , Nanopartículas/química , Polietilenglicoles/química , Polímeros/metabolismo , Propiedades de Superficie , TranscitosisRESUMEN
MUC1 glycopeptides are attractive antigens for anti-cancer vaccine development. One potential drawback in using the native MUC1 glycopeptide for vaccine design is the instability of the O-glycosyl linkage between the glycan and the peptide backbone to glycosidase. To overcome this challenge, a MUC1 glycopeptide mimic has been synthesized with the galactose-galactosamine disaccharide linked with threonine (Thomsen-Friedenreich or Tf antigen) through an unnatural ß-glycosyl bond. The resulting MUC1-ß-Tf had a much-enhanced stability toward a glycosidase capable of cleaving the glycan from the corresponding MUC1 glycopeptide with the natural α-Tf linkage. The MUC1-ß-Tf was subsequently conjugated with a powerful carrier bacteriophage Qß. The conjugate induced high levels of IgG antibodies in clinically relevant human MUC1 transgenic mice, which cross-recognized not only the natural MUC1-α-Tf glycopeptide but also MUC1 expressing tumor cells, supporting the notion that a simple switch of the stereochemistry of the glycan/peptide linkage can be a strategy for anti-cancer vaccine epitope design for glycopeptides.
Asunto(s)
Antígenos de Carbohidratos Asociados a Tumores/química , Vacunas contra el Cáncer/química , Glicopéptidos/química , Mucina-1/química , Animales , Vacunas contra el Cáncer/inmunología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Disacáridos/química , Diseño de Fármacos , Galactosamina/química , Galactosa/química , Humanos , Inmunoglobulina G/química , Inmunoglobulina G/farmacología , Ratones , Ratones Transgénicos , Mucina-1/inmunologíaRESUMEN
In this study, galactosamine-modified poly(ethylene glycol)-poly(lactide) (Gal-PEG-PLA) polymers were synthesized and Gal-PEG-PLA/D-α-tocopherol polyethylene glycol 1000 succinate (TPGS) micelles named as GPP micelles were designed to promote the oral absorption of a hydrophobic drug, curcumin (CUR). CUR-loaded Gal-PEG-PLA/TPGS micelles (CUR@GPP micelles) were fabricated using the thin-film dispersion method. CUR@GPP micelles had a size of about 100 nm, a near-neutral zeta potential, drug loading (DL) of 14.6%, and sustained release properties. GPP micelles with high Gal density (GPP3 micelles) were superior in facilitating uptake in epithelial cells and improving intestinal permeation. In situ intestinal absorption studies suggested that the jejunum and ileum were the best absorption segments in the intestinal tract. Additionally, biodistribution results revealed that GPP3 micelles could be remarkably taken up by the jejunum and ileum. Pharmacokinetics revealed that the maximum plasma concentration (Cmax) and the area under the plasma concentration-time curve from 0 to 24 h (AUC0-24) for CUR@GPP3 micelles were both significantly increased, and that the relative bioavailability of CUR@GPP3 micelles to CUR-loaded mPEG-PLA/TPGS micelles (CUR@PP micelles) was 258.8%. Furthermore, CUR-loaded micelles could reduce damage to the liver and intestinal tissues. This study highlights the importance of Gal content in the design of targeting nanocarrier Gal-modified micelles, which have broad prospects for oral delivery of hydrophobic drugs. Therefore, they could serve as a promising candidate for targeted delivery to the liver.
Asunto(s)
Curcumina/farmacocinética , Galactosamina/química , Micelas , Polietilenglicoles/química , alfa-Tocoferol/química , Administración Oral , Animales , Disponibilidad Biológica , Células CACO-2 , Curcumina/administración & dosificación , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Composición de Medicamentos/métodos , Sistemas de Liberación de Medicamentos/métodos , Endocitosis , Femenino , Humanos , Absorción Intestinal/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/metabolismo , Ratones , Nanopartículas/administración & dosificación , Nanopartículas/química , Ratas , Solubilidad , Distribución TisularRESUMEN
In this study, we describe a novel synthesis of galactosylated lipids by lipase catalysis. Lactitol (Lac), galactose (Gal), or N-acetyl galactosamine (GalNAc) was coupled with cholesterol (CHS) as target head groups by enzyme-catalyzed regioselective esterification to produce three kinds of lipids: CHS-1-Gal, CHS-6-Gal, or CHS-6-GalNAc1. The biological effects of galactosylated lipids carrying different constitutional isomers of the pendent sugar species were investigated. LP-1-Gal (liposomes containing 5.0 molar% of CHS-1-Gal) showed strong binding to tetrameric lectins of Ricinus communis agglutinin (RCA120) in vitro, while LP-6-Gal (liposomes containing 5.0 molar% of CHS-6-Gal) and LP-6-GalNAc (liposomes containing 5.0 molar% of CHS-6-GalNAc) did not. After intravenous injection, LP-6-GalNAc, LP-1-Gal and LP-6-Gal rapidly disappeared from the blood and accumulated rapidly in liver (up to 74.88 ± 4.11%, 58.67 ± 5.75%, and 47.66 ± 4.56% of injected dose/g organ within 4 h, respectively). This is significantly higher than the uptake of unmodified liposomes (Unmod-LP) (18.67 ± 6.07%). Pre-injection of asialofetuin significantly inhibits liver uptake of Gal-liposomes (P < 0.01), with the degree of inhibition appearing in the following order: LP-6-GalNAc (73.29%) > LP-1-Gal (67.06%) > LP-6-Gal (53.61%). More importantly, LP-6-GalNAc was preferentially taken up by hepatocytes and the uptake ratio by parenchymal cells (PC) and nonparenchymal cells (NPC) (PC/NPC ratio) was 11.03 higher than LP-1-Gal (7.32), LP-6-Gal (5.83) and Unmod-LP (2.39). We suggest that liposomes containing the novel galactosylated lipid CHS-6-GalNAc have potential as drug delivery carriers for hepatocyte-selective targeting.
Asunto(s)
Receptor de Asialoglicoproteína/metabolismo , Galactosamina/metabolismo , Galactosa/metabolismo , Hepatocitos/metabolismo , Animales , Receptor de Asialoglicoproteína/química , Femenino , Galactosamina/química , Galactosa/química , Hepatocitos/química , Liposomas/química , Liposomas/metabolismo , Ratones , Ratones Endogámicos , Estructura Molecular , Tamaño de la Partícula , EstereoisomerismoRESUMEN
Since the asialoglycoprotein receptor (also known as the "Ashwell-Morell receptor" or ASGPR) was discovered as the first cellular mammalian lectin, numerous drug delivery systems have been developed and several gene delivery systems associated with multivalent ligands for liver disease targeting are undergoing clinical trials. The success of these systems has facilitated the further study of new ligands with comparable or higher affinity and less synthetic complexity. Herein, we designed two novel trivalent ligands based on the esterification of tris(hydroxymethyl) aminomethane (TRIS) followed by the azide-alkyne Huisgen cycloaddition with azido N-acetyl-d-galactosamine. The presented triazolyl glycoconjugates exhibited good binding to ASGPR, which was predicted using in silico molecular docking and assessed by a surface plasmon resonance (SPR) technique. Moreover, we demonstrated the low level of in vitro cytotoxicity, as well as the optimal spatial geometry and the required amphiphilic balance, for new, easily accessible ligands. The conjugate of a new ligand with Cy5 dye exhibited selective penetration into HepG2 cells in contrast to the ASGPR-negative PC3 cell line.
Asunto(s)
Receptor de Asialoglicoproteína/metabolismo , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Alquinos/química , Receptor de Asialoglicoproteína/química , Azidas , Técnicas de Química Sintética , Diseño de Fármacos , Esterificación , Galactosamina/química , Células Hep G2 , Humanos , Ligandos , Metano/síntesis química , Metano/química , Metano/metabolismo , Metano/farmacología , Simulación del Acoplamiento Molecular , Células PC-3 , Conformación ProteicaRESUMEN
Plant polysaccharides gained extended scientific attention for their immunomodulatory effect. However, few scientific studies structurally defined polysaccharides in relation to their biological modifier response. Therefore, the study explored the effect of structurally identified isolated macromolecules from Aloe arborescens against cytokine modulation (interferon [IFN-γ], interleukins [IL-2 and IL-12], and tumor necrosis factor [TNF-α]) in vitro. The structures were elucidated by GC, GPC, FT-IR spectroscopy, 1D NMR, COSY, HMBC, and HSQC. Two acetylated glucomannans (AANP4 and AAAP6), one deoxy-glucogalactan (AANP5), and one deoxy-N-acetyl-[1-4]-galactosamine (AANP2) were isolated. The results showed significant induction for all cytokines and the most potent component was AAAP6; acetylated phenolic glucomannan with a (1 â 3)-linked glucose-mannose and (1 â 4)-linked mannose backbone, which stimulated IL-12 by more than 10-fold compared with phytohemagglutinin (positive control). In conclusion, A. arborescens polysaccharides could be a landmark for development of effective immunotherapeutics against cancer and chronic inflammatory conditions.
Asunto(s)
Aloe/química , Galactosamina/química , Factores Inmunológicos/química , Polisacáridos/química , Acetilación , Estructura Molecular , Fitoquímicos/química , Hojas de la Planta/química , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
Using 3-O-benzoyl-4,6-O-di-tert-butylsilylidene-2-azido-2-deoxy-selenogalactoside, biotinylated oligo-α-(1 â 4)-d-galactosamines comprising from two to six GalN units were prepared for the first time together with their N-acetylated derivatives. The combination of blocking groups used herein provided stereocontrol for the α-stereospecific glycosylation, to show also high efficiency of phenyl 2-azido-2-deoxy-selenogalactosides as glycosyl donors. The obtained glycoconjugates are related to fragments of exopolysaccharide galactosaminogalactan (GG) found in Aspergillus fumigatus, which is the most important airborne human fungal pathogen in industrialized countries. The synthesized glycoconjugates were arrayed on streptavidin-coated plates and used to investigate the GG epitopes recognized by mouse monoclonal antibodies against GG and by human antibodies in the sera of patients with aspergillosis. The obtained data showed that the oligo-α-(1 â 4)-d-galactosamines and their N-acetylated derivatives allowed the first precise analysis of the specificity of the antibody responses to this extremely complex fungal polysaccharide.
Asunto(s)
Biotinilación , Galactosamina/química , Acetilación , Galactosamina/inmunología , Humanos , Estereoisomerismo , Relación Estructura-ActividadRESUMEN
Nanoparticles have been extensively studied for drug delivery and targeting to specific organs. The functionalization of the nanoparticle surface by site-specific ligands (antibodies, peptides, saccharides) can ensure efficient recognition and binding with relevant biological targets. One of the main challenges in the development of these decorated nanocarriers is the accurate quantification of the amount of ligands on the nanoparticle surface. In this study, nanostructured lipid carriers (NLC) were functionalized with N-acetyl-D-galactosamine (GalNAc) units, known to target the asialoglycoprotein receptor (ASGPR). Different molar percentages of GalNAc-functionalized surfactant (0%, 2%, 5%, and 14%) were used in the formulation. Based on ultra-high-performance liquid chromatography separation and evaporative light-scattering detection (UPLC-ELSD), an analytical method was developed to specifically quantify the amount of GalNAc units present at the NLC surface. This method allowed the accurate quantification of GalNAc surfactant and therefore gave some insights into the structural parameters of these multivalent ligand systems. Our data show that the GalNAc decorated NLC possess large numbers of ligands at their surface and suitable distances between them for efficient multivalent interaction with the ASGPR, and therefore promising liver-targeting efficiency.
Asunto(s)
Portadores de Fármacos/química , Galactosamina/química , Lípidos/química , Nanopartículas/química , Tensoactivos/químicaRESUMEN
As an important glycoprotein of the lectin family, soybean agglutinin (SBA) is an anti-nutritional factor with considerable toxic and side effects and plays a significant role in tumor analysis. In order to achieve the sensitive detection of SBA, a sandwich-structured electrochemiluminescence (ECL) biosensor was constructed using carboxylated carbon nitride (C-g-C3N4) as luminophore and D-galactosamine (galM) as a recognition element. A glassy carbon electrode (GCE) was modified with Au nanoparticles (Au NPs) for capturing the galM via Au-N bond, and further capturing the target SBA by specific recognition between galM and SBA. In the presence of SBA, the composite C-g-C3N4-galM was immobilized onto the electrode. With the increase in the concentration of SBA, the ECL signal from C-g-C3N4 increased, thus achieving a signal-on detection of SBA. The linear range of the biosensor was 1.0 ng/mL~10 µg/mL and detection limit for SBA was as low as 0.33 ng/mL. In this construction strategy, C-g-C3N4 not only acted as an excellent signal probe, but also as an immobilization matrix to easily achieve a high loading of the small molecule recognition element galM. This strategy provides a simple alternative SBA detection platform. Graphical abstract.
Asunto(s)
Galactosamina/química , Grafito/química , Sustancias Luminiscentes/química , Nitrilos/química , Lectinas de Plantas/análisis , Proteínas de Soja/análisis , Técnicas Biosensibles/métodos , Ácidos Carboxílicos/química , Técnicas Electroquímicas/métodos , Oro/química , Humanos , Límite de Detección , Mediciones Luminiscentes/métodos , Nanopartículas del Metal/química , Lectinas de Plantas/sangre , Proteínas de Soja/sangreRESUMEN
BACKGROUND: Pre-clinical toxicology studies of human Gc-protein (vitamin D binding protein) are of special interest as to the transport of vitamin D and its biological activities. We have demonstrated that the oral application of a special dimeric vitamin D complex reduces oxidative stress and increases the quality of life in autistic children. Therefore, safety and toxic effects of two dimeric cholecalciferol-N-acetyl-galactosamine-albumin complexes were evaluated in increasing intravenous (iv.) vitamin D levels administered in a pre-clinical trial in mice over a 5-week period. METHODS: Over a period of 5 weeks, two times a week, mice received iv. administration of one of the following: (a) 1.2 IE of vitamin D-N-acetyl-galactosamine-albumin (Vitamin D3 NAGA, ImmunoD® group), (b) 1.2 IE of vitamin-D-poly-N-acetyl-galactosamine-albumin (Poly-Nac group), or (c) isotonic saline solution (sham group). Before and after the trial, red and white blood cell panels (RBS, WBC and platelets) were determined. Furthermore, vitamin D levels, electrolytes, and C-reactive protein levels were measured directly before sacrificing. RESULTS: No toxic effects were observed during iv. injection with dimeric vitamin D complexes, neither in the sham group, nor in the two treatment groups. Vitamin D levels increased significantly within 5 weeks in the Poly-Nac group (26.6 ± 8.8 ng/mL; p = 0.001) compared to the sham group (3.1 ± 0.9 ng/mL), and the Poly-Nac group to the ImmunoD group (7.0 ± 3.6 ng/mL; p = 0.003). A significant increase of vitamin D was also obtained in favor of the ImmunoD group compared to the sham (p = 0.03). Electrolytes (K, Na, Cl, Mg, Ca) and C-reactive protein showed no significant differences after administration in all three mice groups. Also, no significant differences were observed between these three groups in the WBC and RBC blood panels. CONCLUSIONS: The two dimeric vitamin D complexes used in this pre-clinical study showed no side or toxic effects after iv. administration in mice, but a sole increase in vitamin D levels without any change in electrolytes or blood cells. Therefore, we assume this newly developed composition to be safe in oral or iv.-administration and further pre-clinical studies can be conducted to evaluate the value in treatment of various diseases related to vitamin D deficiencies.
Asunto(s)
Albúminas , Colecalciferol , Galactosamina , Deficiencia de Vitamina D , Animales , Ratones , Albúminas/administración & dosificación , Albúminas/química , Colecalciferol/administración & dosificación , Colecalciferol/sangre , Colecalciferol/química , Dimerización , Esquema de Medicación , Recuento de Eritrocitos , Galactosamina/administración & dosificación , Galactosamina/química , Inyecciones Intravenosas , Recuento de Leucocitos , Resultado del Tratamiento , Deficiencia de Vitamina D/sangre , Deficiencia de Vitamina D/tratamiento farmacológicoRESUMEN
An unnatural monosaccharide with a C6-azide, Ac36AzGalNAc, has been developed as a potent and selective probe for O-GlcNAc-modified proteins. Combined with click chemistry, we demonstrate that Ac36AzGalNAc can robustly label O-GlcNAc glycosylation in a wide range of cell lines. Meanwhile, cell imaging and LC-MS/MS proteomics verify its selective activity on O-GlcNAc. More importantly, the protocol presented here provides a general methodology for tracking, capturing and identifying unnatural monosaccharide modified proteins in cells or cell lysates.
Asunto(s)
Galactosamina/química , Sondas Moleculares/química , N-Acetilglucosaminiltransferasas/análisis , beta-N-Acetilhexosaminidasas/análisis , Animales , Células Cultivadas , Galactosamina/análogos & derivados , Galactosamina/síntesis química , Humanos , Ratones , Sondas Moleculares/síntesis química , Estructura Molecular , N-Acetilglucosaminiltransferasas/metabolismo , beta-N-Acetilhexosaminidasas/metabolismoRESUMEN
Multivalent ligand-receptor interactions play essential roles in biological recognition and signaling. As the receptor arrangement on the cell surface can alter the outcome of cell signaling and also provide spatial specificity for ligand binding, controlling the presentation of ligands has become a promising strategy to manipulate or selectively target protein receptors. The lack of adjustable universal tools to control ligand positions at the size of a few nanometers has prompted the development of polyproline tri-helix macrocycles as scaffolds to present ligands in designated patterns. Model lectin Helix pomatia agglutinin has shown selectivity toward the matching GalNAc ligand pattern matching its binding sites arrangement. The GalNAc pattern selectivity is also observed on intact asialoglycoprotein receptor oligomer on human hepatoma cells showing the pattern-selective interaction can be achieved not only on isolated protein oligomers but also the receptors arranged on the cell surface. As the scaffold design allows convenient creation of versatile ligand patterns, it can be expected as a promising tool to probe the arrangement of receptors on the cell surface and as nanomedicine to manipulate signaling or cell recognition.
Asunto(s)
Lectinas/química , Lectinas/metabolismo , Compuestos Macrocíclicos/química , Nanopartículas/química , Tamaño de la Partícula , Péptidos/química , Multimerización de Proteína , Secuencia de Aminoácidos , Receptor de Asialoglicoproteína/química , Línea Celular Tumoral , Ciclización , Galactosamina/química , Glicoconjugados/síntesis química , Glicoconjugados/química , Humanos , Ligandos , Péptidos/síntesis química , Unión Proteica , Espectroscopía de Protones por Resonancia MagnéticaRESUMEN
The F9/Yde/Fml pilus, tipped with the FmlH adhesin, has been shown to provide uropathogenic Escherichia coli (UPEC) a fitness advantage in urinary tract infections (UTIs). Here, we used X-ray structure guided design to optimize our previously described ortho-biphenyl Gal and GalNAc FmlH antagonists such as compound 1 by replacing the carboxylate with a sulfonamide as in 50. Other groups which can accept H-bonds were also tolerated. We pursued further modifications to the biphenyl aglycone resulting in significantly improved activity. Two of the most potent compounds, 86 (IC50 = 0.051 µM) and 90 (IC50 = 0.034 µM), exhibited excellent metabolic stability in mouse plasma and liver microsomes but showed only limited oral bioavailability (<1%) in rats. Compound 84 also showed a good pharmacokinetic (PK) profile in mice after IP dosing with compound exposure above the IC50 for 6 h. These new FmlH antagonists represent new antivirulence drugs for UTIs.
Asunto(s)
Adhesinas de Escherichia coli/química , Compuestos de Bifenilo/química , Diseño de Fármacos , Galactosamina/química , Galactosa/química , Adhesinas de Escherichia coli/metabolismo , Administración Oral , Animales , Galactosamina/farmacocinética , Galactosamina/uso terapéutico , Galactosa/farmacocinética , Semivida , Humanos , Ratones , Microsomas Hepáticos/metabolismo , Ratas , Relación Estructura-Actividad , Infecciones Urinarias/tratamiento farmacológico , Escherichia coli UropatógenaRESUMEN
Chondroitin sulfate E (CS-E) plays a crucial role in diverse processes ranging from viral infection to neuroregeneration. Its regiospecific sulfation pattern, generated by N-acetylgalactosamine 4-sulfate 6-O-sulfotransferase (GalNAc4S-6ST), is the main structural determinant of its biological activity. Inhibitors of GalNAc4S-6ST can serve as powerful tools for understanding physiological functions of CS-E and its potential therapeutic leads for human diseases. A family of new 4-acylamino-ß-GalNAc derivatives and 4-azido-ß-GalNAc derivatives were synthesized for their potential application as inhibitors of GalNAc4S-6ST. The target compounds were evaluated for their inhibitory activities against GalNAc4S-6ST. The results revealed that 4-pivaloylamino- and 4-azido-ß-GalNAc derivatives displayed evident activities against GalNAc4S-6ST with IC50 value ranging from 0.800 to 0.828 mM. They showed higher activities than benzyl D-GalNAc4S that was used as control.
Asunto(s)
Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/farmacología , Galactosamina/síntesis química , Galactosamina/farmacología , Sulfotransferasas/antagonistas & inhibidores , Amidas/química , Animales , Inhibidores Enzimáticos/química , Galactosamina/química , Humanos , Sulfotransferasas/metabolismoRESUMEN
A polymer of Galactosamine-hyaluronic acid-Vitamin E succinate (Gal-HA-VES) was designed to prepare multifunctional self-assembled micelles for delivery of Norcantharidin (NCTD) to Hepatic carcinoma. NCTD/Gal-HA-VES showed higher cytotoxicity toward CD44-overexpressing MCF-7 cells, MCF-7/Adr cells and ASGP-R overexpressing HepG2 cells, consistent with the enhanced cellular uptake in the selected cell models, indicating Gal-HA-VES micelles were taken up in MCF-7 and HepG2 cells by CD44 and ASGPR receptor mediated endocytosis, respectively. Moreover, the accumulation of Rhodamine 123 demonstrated that Gal-HA-VES has the same action of TPGS as a P-glycoprotein inhibitor blocked drug efflux-related MDR mechanism in resistant MCF-7/Adr cells. The Cell apoptosis assays indicated that NCTD/Gal-HA-VES were more effective in triggering apoptosis, compared with free NCTD or NCTD/HA-VES groups. In vivo study demonstrated that NCTD/Gal-HA-VES group exhibited enhanced tumor targeting and antitumor activity with lower systemic toxicity. Hence NCTD/Gal-HA-VES micelles system can achieve significant tumor targeting and effective treatment of hepatic carcinoma.
Asunto(s)
Antineoplásicos/farmacología , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Carcinoma Hepatocelular/tratamiento farmacológico , Galactosamina/química , Ácido Hialurónico/química , Neoplasias Hepáticas/tratamiento farmacológico , alfa-Tocoferol/análogos & derivados , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Compuestos Bicíclicos Heterocíclicos con Puentes/química , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Sistemas de Liberación de Medicamentos , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Células Hep G2 , Humanos , Neoplasias Hepáticas Experimentales/tratamiento farmacológico , Células MCF-7 , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Micelas , Estructura Molecular , Relación Estructura-Actividad , alfa-Tocoferol/químicaRESUMEN
BACKGROUND: Resveratrol (RES) is a natural anti-inflammatory and antioxidant compound with poor water solubility and oral bioavailability. The present study takes the advantages of nanocarriers combined with a ligand (galactose) anchoring to orally deliver RES in an attempt to improve its bioavailability and pharmacological activity. METHODS: RES-loaded galactosylated nanoparticles (RES-GNPs) were prepared by solvent diffusion technique using poly(lactic-co-glycolic acid), synthesized N-oleoyl-d-galactosamine and Tween 80. RES-GNPs were characterized by particle size, morphology, entrapment efficiency (EE) and in vitro release. Oral bioavailability and in vitro anti-inflammatory activity were investigated in rats and lipopolysaccharides-induced RAW 264.7 cells, respectively. RESULTS: The resulting RES-GNPs were 108.4 nm around in particle size with a polydispersity index of 0.217. Furthermore, RES-GNPs possessed a high EE and a slow drug release in water. After oral administration, RES-GNPs significantly enhanced the oral bioavailability of RES, up to 335.7% relative to RES suspensions. In situ single-pass intestinal perfusion and cellular uptake experiments showed that GNPs could improve the intestinal permeability and transcellular transport of RES. Moreover, the anti-inflammatory efficacy of RES-GNPs in RAW 264.7 cells model was superior to free RES and RES-GNPs. CONCLUSION: The results indicate that RES-GNPs can effectively promote the intestinal absorption of RES and strengthen its bioactivity, which may be a promising system for the treatment of inflammatory diseases.