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1.
Biomacromolecules ; 23(9): 3990-4003, 2022 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-35960547

RESUMO

The hierarchical microstructure evolution of an emerging biobased odd-odd polyamide 5,13 (PA5,13) films under the thermo-mechanical field, stepping from hydrogen bond (H-bond) arrangement to the crystalline morphology, has been investigated systematically. It is found that the reorganization of H-bonds under the thermo-mechanical field plays a crucial role in the crystallization of PA5,13. Especially, it is revealed that the crystallization process under the thermo-mechanical field develops along the chain axis direction, while lamellar fragmentation occurs perpendicular to the chain axis. Consequently, a stable and well-organized H-bond arrangement and lengthened lamellae with significant orientation have been constructed. Laudably, an impressive tensile strength of about 500 MPa and modulus of about 4.7 GPa are thus achieved. The present study could provide important guidance for the industrial-scale manufacture of high-performance biobased odd-odd PAs with long polymethylene segment in the dicarboxylic unit combined with a large difference between the polymethylene segments in the dicarboxylic and diamine units.


Assuntos
Nylons , Ligação de Hidrogênio , Resistência à Tração
2.
J Am Chem Soc ; 141(10): 4406-4411, 2019 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-30801185

RESUMO

The precise and highly efficient drug delivery of nanomedicines into lesions remains a critical challenge in clinical translational research. Here, an autocatalytic morphology transformation platform is presented for improving the tumor-specific accumulation of drugs by kinetic control. The in situ reorganization of prodrug from nanoparticle to ß-sheet fibrous structures for targeted accumulation is based on nucleation-based growth kinetics. During multiple administrations, the autocatalytic morphology transformation can be realized for skipping slow nucleating process and constructing the bulky nanoassembly instantaneously, which has been demonstrated to induce the cumulative effect of prodrug. Furthermore, the sustained drug release from fibrous prodrug depot in the tumor site inhibits the tumor growth efficiently. The autocatalytic morphology transformation strategy in vivo offers a novel perspective for targeted delivery strategy by introducing chemical kinetics and shows great potential in disease theranostics.


Assuntos
Antineoplásicos/farmacologia , Camptotecina/farmacologia , Portadores de Fármacos/química , Nanofibras/química , Peptídeos/química , Animais , Antineoplásicos/metabolismo , Camptotecina/análogos & derivados , Camptotecina/metabolismo , Catepsina B/metabolismo , Preparações de Ação Retardada , Portadores de Fármacos/metabolismo , Liberação Controlada de Fármacos , Feminino , Células HeLa , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanopartículas/química , Nanopartículas/metabolismo , Peptídeos/metabolismo , Polietilenoglicóis/química , Pró-Fármacos/química , Pró-Fármacos/metabolismo , Multimerização Proteica , Proteólise
3.
J Am Chem Soc ; 141(18): 7235-7239, 2019 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-31010287

RESUMO

The morphology controlled molecular assemblies play vital roles in biological systems. Here we present endogenous reactive oxygen species (ROS)-triggered morphology transformation of polymer-peptide conjugates (PPCs) for cooperative interaction with mitochondria, exhibiting high tumor therapeutic efficacy. The PPCs are composed of (i) a ß-sheet-forming peptide KLVFF conjugated with poly(ethylene glycol) through ROS-cleavable thioketal, (ii) a mitochondria-targeting cytotoxic peptide KLAK, and (iii) a poly(vinyl alcohol) backbone. The self-assembled PPCs nanoparticles can enter cells and target mitochondria. Because of overgenerated ROS around mitochondria in most cancer cells, the thioketal linker can be cleaved, leading to transformation from nanoparticles to fibrous nanostructures. As a result, the locational nanofibers with exposure of KLAK exhibit enhanced multivalent cooperative interactions with mitochondria, which causes selective cytotoxicity against cancer cells and powerful tumor suppression efficacy in vivo. As the first example of ROS-triggered intracellular transformation, the locational assembly strategy in vivo may provide a new insight for disease diagnosis and therapy through enhanced interaction with targeting site.


Assuntos
Antineoplásicos/metabolismo , Mitocôndrias/metabolismo , Peptídeos/metabolismo , Álcool de Polivinil/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Camundongos , Mitocôndrias/química , Neoplasias Experimentais/diagnóstico por imagem , Neoplasias Experimentais/tratamento farmacológico , Imagem Óptica , Peptídeos/química , Peptídeos/farmacologia , Álcool de Polivinil/química , Álcool de Polivinil/farmacologia , Espécies Reativas de Oxigênio/química
4.
Biomacromolecules ; 20(2): 882-892, 2019 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-30621390

RESUMO

Despite recent advances in tumor treatment through cancer immunotherapy, the efficacy of this approach remains to be improved. Looking forward to high rates of objective clinical response, cancer immunotherapy combined with chemotherapy has gained increasing attention recently. Here, we constructed liposomes with matrix metalloproteinases (MMPs) responsive moiety and PD-L1 inhibitor conjugate combine with low dose chemotherapy to achieve enhanced antitumor efficacy. Upon introduction of the pH-responsive polymer to LPDp, the coassembly could be almost stable in physiological conditions and tumor microenvironments and release the loaded cargos at the lysosome. MMP-2 enzyme extracellularly secreted by the B16F10 cells could cleave the cross-linker and liberate the PD-L1 inhibitor effectively disrupting the PD-1/PD-L1 interaction in vitro. Low dose DOX encapsulated in the LPDp was capable of sensitizing B16F10 cells to CTLs by inducing overexpression of M6PR on tumor cell membranes. In comparison with free PD-L1 inhibitor, LPDp improved the biodistribution and on-demand release of the peptide inhibitor in tumor regions following administration. LPDp achieved the optimal tumor suppression efficiency (∼78.7%), which demonstrated the significantly enhanced antitumor effect ( P < 0.01) than that of LPp (∼57.5%) as well as that of LD (<40%), attributing to synergistic contribution from the substantial increase in M6PR expression on tumor cells and the blockade of immune checkpoints. This strategy provides a strong rationale for combining standard-of-care chemotherapy with relative nontoxic and high specific immunotherapy.


Assuntos
Antineoplásicos/administração & dosagem , Antígeno B7-H1/antagonistas & inibidores , Lipossomos/química , Metaloproteinases da Matriz/metabolismo , Polímeros Responsivos a Estímulos/química , Microambiente Tumoral , Animais , Linhagem Celular Tumoral , Doxorrubicina/administração & dosagem , Liberação Controlada de Fármacos , Tratamento Farmacológico/métodos , Concentração de Íons de Hidrogênio , Imunoterapia/métodos , Camundongos
5.
Acta Pharmacol Sin ; 40(1): 143-150, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29950614

RESUMO

Mesangial proliferative glomerulonephritis (MsPGN), one of the most common glomerulonephritis pathological types, often leads to end-stage renal disease over a prolonged period. But the current treatment of MsPGN is non-specific and causes serious side effects, thus novel therapeutics and targeting strategies are urgently demanded. By combining the advantages of PEG-PLGA nanoparticles and the size selection mechanism of renal glomerulus, we designed and developed a novel PEG-PLGA nanoparticle delivery system capable of delivering dexamethasone acetate (A-DEX) into glomerular mesangium. We determined that 90 nm was the optimum size to encapsulate A-DEX for glomerular mesangium targeting based on the size-selection mechanism of glomerulus. After intravenous administration in rats, 90 nm DiD-loaded NPs were found to accumulate to a greater extent in the kidney and kidney cortex compared with the free DiD solution. The 90 nm A-DEX NPs are also more stable at room temperature and showed a sustained release pattern. In rat glomerular mesangial cells (HBZY-1) in vitro, we found that the uptake of 90 nm A-DEX NPs was both temperature-dependent and energe-dependent, and they were mostly engulfed via clathrin-dependent endocytosis pathways. In summary, we have successfully developed a glomerular mesangium-targeted PEG-PLGA NPs, which is potential for the treatment of MsPGN.


Assuntos
Dexametasona/análogos & derivados , Portadores de Fármacos/química , Mesângio Glomerular/metabolismo , Nanopartículas/química , Poliésteres/química , Polietilenoglicóis/química , Animais , Dexametasona/metabolismo , Desenho de Fármacos , Liberação Controlada de Fármacos , Tamanho da Partícula , Ratos Sprague-Dawley , Distribuição Tecidual
6.
Acta Pharmacol Sin ; 40(11): 1448-1456, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31015736

RESUMO

Gemcitabine (Gem) is a standard first-line treatment for pancreatic cancer (PC). However, its chemotherapeutic efficacy is hampered by various limitations such as short half-life, metabolic inactivation, and lack of tumor localizing. We previously synthesized a lipophilic Gem derivative (Gem formyl hexadecyl ester, GemC16) that exhibited improved antitumor activity in vitro. In this study, a target ligand N,N-dimethyl-1,3-propanediamine was conjugated to 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[hydroxyl succinimidyl (polyethylene glycol-2000)] (DSPE-PEG-NHS) to form DSPE-PEG-2N. Then, pancreas-targeting liposomes (2N-LPs) were prepared using the film dispersion-ultrasonic method. GemC16-loaded 2N-LPs displayed near-spherical shapes with an average size distribution of 157.2 nm (polydispersity index (PDI) = 0.201). The encapsulation efficiency of GemC16 was up to 97.3% with a loading capacity of 8.9%. In human PC cell line (BxPC-3) and rat pancreatic acinar cell line (AR42J), cellular uptake of 2N-LPs was significantly enhanced compared with that of unmodified PEG-LPs. 2N-LPs exhibited more potent in vitro cytotoxicity against BxPC-3 and AR42J cell lines than PEG-LPs. After systemic administration in mice, 2N-LPs remarkably increased drug distribution in the pancreas. In an orthotopic tumor mouse model of PC, GemC16-bearing liposomes were more effective in preventing tumor growth than free GemC16. Among these treatments, 2N-LPs showed the best curative effect. Together, 2N-LPs represent a promising nanocarrier to achieve pancreas-targeting drug delivery, and this work would provide new ideas for the chemotherapy of PC.


Assuntos
Antineoplásicos/uso terapêutico , Desoxicitidina/análogos & derivados , Portadores de Fármacos/química , Lipossomos/química , Pâncreas/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Desoxicitidina/administração & dosagem , Desoxicitidina/uso terapêutico , Diaminas/síntese química , Diaminas/química , Diaminas/toxicidade , Portadores de Fármacos/síntese química , Portadores de Fármacos/toxicidade , Sistemas de Liberação de Medicamentos/métodos , Lipossomos/síntese química , Lipossomos/toxicidade , Camundongos Endogâmicos C57BL , Pâncreas/patologia , Neoplasias Pancreáticas/patologia , Fosfatidiletanolaminas/síntese química , Fosfatidiletanolaminas/química , Fosfatidiletanolaminas/toxicidade , Polietilenoglicóis/síntese química , Polietilenoglicóis/química , Polietilenoglicóis/toxicidade , Gencitabina
7.
Nano Lett ; 18(10): 6577-6584, 2018 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-30251542

RESUMO

Nanotherapeutics have encountered some bottleneck problems in cancer therapy, such as poor penetration and inefficient accumulation in tumor site. We herein developed a novel strategy for deep tissue penetration in molecular level and near-infrared (NIR) laser guided in situ self-assembly to solve these challenges. For the proof-of-concept study, we synthesized the polymer-peptide conjugates (PPCs) composed of (i) poly(ß-thioester) as thermoresponsive backbone, (ii) functional peptides (cytotoxic peptide and cell-penetrating peptide), and (iii) the NIR molecule with photothermal property. The PPCs in the molecular level with small size (<10 nm) can penetrate deeply into the interior of the tumor at body temperature. Under the irradiation of NIR laser, the temperature rise induced by photothermal molecules led to the intratumoral self-assembly of thermoresponsive PPCs. The resultant spherical nanoparticles can accumulate in tumor and enter cells effectively, inducing cell apoptosis by destroying mitochondria membrane. Through the site-specific size control, a variety of merits of PPCs are realized including deep tumor penetration, enhanced accumulation, and cellular internalization in vivo. Taking advantage of the NIR guided in situ assembly strategy, numerous polymeric or nanoscaled therapeutics with high anticancer activity can be exploited.


Assuntos
Doxorrubicina/administração & dosagem , Sistemas de Liberação de Medicamentos , Nanopartículas/administração & dosagem , Neoplasias/tratamento farmacológico , Linhagem Celular Tumoral , Doxorrubicina/química , Ouro/química , Humanos , Hipertermia Induzida/métodos , Raios Infravermelhos , Lasers , Nanopartículas/química , Neoplasias/patologia , Polímeros/química
8.
Angew Chem Int Ed Engl ; 58(14): 4632-4637, 2019 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-30695128

RESUMO

In cancer treatment, the unsatisfactory solid-tumor penetration of nanomaterials limits their therapeutic efficacy. We employed an in vivo self-assembly strategy and designed polymer-peptide conjugates (PPCs) that underwent an acid-induced hydrophobicity increase with a narrow pH-response range (from 7.4 to 6.5). In situ self-assembly in the tumor microenvironment at appropriate molecular concentrations (around the IC50 values of PPCs) enabled drug delivery deeper into the tumor. A cytotoxic peptide KLAK, decorated with the pH-sensitive moiety cis-aconitic anhydride (CAA), and a cell-penetrating peptide TAT were conjugated onto poly(ß-thioester) backbones to produce PT-K-CAA, which can penetrate deeply into solid tumors owing to its small size as a single chain. During penetration in vivo, CAA responds to the weak acid, leading to the self-assembly of PPCs and the recovery of therapeutic activity. Therefore, a deep-penetration ability for enhanced cancer therapy is provided by this in vivo assembly strategy.


Assuntos
Antineoplásicos/farmacologia , Peptídeos/farmacologia , Polímeros/farmacologia , Microambiente Tumoral/efeitos dos fármacos , Ácido Aconítico/administração & dosagem , Ácido Aconítico/análogos & derivados , Ácido Aconítico/química , Ácido Aconítico/farmacologia , Administração Intravenosa , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Concentração de Íons de Hidrogênio , Camundongos , Tamanho da Partícula , Peptídeos/administração & dosagem , Peptídeos/química , Polímeros/administração & dosagem , Polímeros/química , Propriedades de Superfície
9.
Bioconjug Chem ; 28(6): 1709-1721, 2017 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-28485595

RESUMO

Nanoscaled polymer-peptide conjugates (PPCs) containing both functional peptides and synthetic polymer comprise a new family of biomaterials that can circumvent the limitation of peptides alone. Our previous work showed that PPCs with the therapeutic peptide KLAK, especially PPCs with shorter PEG spacers and a higher degree of polymerization, exhibit enhanced antitumor effects through disrupting mitochondrial membranes. However, as PPCs have a spherical nanostructure (45-60 nm), this may have other effects besides the conjugated therapeutic peptide KLAK itself when they enter cancer cells. In this research, we compared the proteome differences of U87 cells treated with KLAK, polymer, and their conjugates (P-KLAK) through quantitative proteomics technology. The result reveals that proteins involved in oxidative stress response and the Nrf2/ARE pathway were significantly up-regulated after P-KLAK treatment. Moreover, the overexpression of sequestosome 1, a protein substrate that is selectively incorporated into the formation of autophagosome and degraded by autophagy, is found in our study and has not been reported previously in the study of KLAK toxicity. Additional experiments suggest that upon endocytosis, P-KLAK causes lysosome impairment and results in autophagosomes accumulation. Hence, P-KLAK might induce U87 cell death by autophagy blockage due to lysosome impairment as well as mitochondria damage synergistically.


Assuntos
Neoplasias/tratamento farmacológico , Peptídeos/química , Polímeros/química , Autofagossomos/metabolismo , Autofagia/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Lisossomos/efeitos dos fármacos , Mitocôndrias/patologia , Fator 2 Relacionado a NF-E2 , Neoplasias/patologia , Estresse Oxidativo , Peptídeos/uso terapêutico , Polímeros/uso terapêutico , Proteômica
10.
Biomacromolecules ; 18(4): 1249-1258, 2017 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-28269979

RESUMO

The stimuli-responsive polymeric nanocarriers have been studied extensively, and their structural changes in cells are important for the controlled intracellular drug release. The present work reported RGD-dextran/purpurin 18 conjugates with pH-responsive phenylboronate as spacer for monitoring the structural change of nanovehicles through ratiometric photoacoustic (PA) signal. Phenylboronic acid modified purpurin 18 (NPBA-P18) could attach onto the RGD-decorated dextran (RGD-Dex), and the resulting RGD-Dex/NPBA-P18 (RDNP) conjugates with different molar ratios of RGD-Dex and NPBA-P18 were prepared. When the moles of NPBA-P18 were equivalent to more than triple of RGD-Dex, the single-stranded RDNP conjugates could self-assemble into nanoparticles in aqueous solution due to the fairly strong hydrophobicity of NPBA-P18. The pH-responsive aggregations of NPBA-P18 were investigated by UV-vis, fluorescence, and circular dichroism spectra, as well as transmission electron microscope. Based on distinct PA signals between monomeric and aggregated state, ratiometric PA signal of I750/I710 could be presented to trace the structural change progress. Compared with RDNP single chains, the nanoparticles exhibited effective cellular internalization through endocytosis pathway. Furthermore, the nanoparticles could form well-ordered aggregates responding to intracellular acidic environment, and the resulting structural change was also monitored by ratiometric PA signal. Therefore, the noninvasive PA approach could provide a deep insight into monitoring the intracellular structural change process of stimuli-responsive nanocarriers.


Assuntos
Ácidos Borônicos/química , Citoplasma/química , Dextranos/química , Oligopeptídeos/química , Técnicas Fotoacústicas , Porfirinas/química , Portadores de Fármacos , Liberação Controlada de Fármacos , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética , Nanopartículas/química , Polímeros/química
11.
Acta Pharmacol Sin ; 38(3): 424-433, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28112183

RESUMO

Scopoletin is an active coumarin possessing a variety of pharmacological activities, including anti-hyperuricemic effect, but with poor solubility. To improve its oral bioavailability, we attempted to encapsulate scopoletin into Soluplus micelles (Soluplus-based scopoletin micelles, Sco-Ms) and evaluated the hypouricemic action of Sco-Ms. Sco-Ms were prepared using a thin-film hydration method. Sco-Ms displayed near spherical shapes with an average size of 59.4±2.4 nm (PDI=0.08±0.02). The encapsulation efficiency of scopoletin was 87.3%±1.5% with a loading capacity of 5.5%±0.1%. Sco-Ms were further characterized using transmission electron microscopy, powder X-ray diffraction, Fourier transform infrared techniques and scanning electron microscopy. After oral administration in rats, Sco-Ms exhibited significantly improved absorption in each intestinal segment compared to free scopoletin, with the duodenum and jejunum being the main absorption regions. In rats administered Sco-Ms (at an equivalent dose of free scopoletin of 100 mg/kg, po), the AUC0-∞ and Cmax of Sco-Ms were 4.38- and 8.43-fold, respectively, as large as those obtained following administration of free scopoletin. After oral administration in rats, Sco-Ms did not alter the tissue distributions of scopoletin, but significantly increased the scopoletin levels in the liver. In potassium oxonate-induced hyperuricemic mice, oral administration of Sco-Ms (at an equivalent dose of free scopoletin of 300 mg/kg) reduced the serum uric acid concentration to the normal level. The results suggest that Soluplus-based micelle system greatly improves the bioavailability of poorly water-soluble drugs, such as scopoletin, and represents a promising strategy for their oral delivery.


Assuntos
Hiperuricemia/tratamento farmacológico , Polietilenoglicóis/química , Polivinil/química , Escopoletina/administração & dosagem , Escopoletina/farmacologia , Administração Oral , Animais , Disponibilidade Biológica , Masculino , Camundongos Endogâmicos ICR , Micelas , Ratos Sprague-Dawley , Escopoletina/farmacocinética
12.
Small ; 12(21): 2921-31, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27120078

RESUMO

In drug delivery systems, pH-sensitive polymers are commonly used as drug carriers, and significant efforts have been devoted to the aspects of controlled delivery and release of drugs. However, few studies address the possible autophagic effects on cells. Here, for the first time, using a fluorescent autophagy-reporting cell line, this study evaluates the autophagy-induced capabilities of four types of pH-sensitive polymeric nanoparticles (NPs) with different physical properties, including size, surface modification, and pH-sensitivity. Based on experimental results, this study concludes that pH-sensitivity is one of the most important factors in autophagy induction. In addition, this study finds that variation of concentration of NPs could cause different autophagic effect, i.e., low concentration of NPs induces autophagy in an mTOR-dependent manner, but high dose of NPs leads to autophagic cell death. Identification of this tunable autophagic effect offers a novel strategy for enhancing therapeutic effect in cancer therapy through modulation of autophagy.


Assuntos
Autofagia/efeitos dos fármacos , Lisossomos/química , Nanopartículas/química , Polímeros/química , Polímeros/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Humanos , Concentração de Íons de Hidrogênio , Células MCF-7
13.
Biomacromolecules ; 17(5): 1643-52, 2016 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-27023216

RESUMO

One of the major challenges in current cancer therapy is to maximize therapeutic effect and evaluate tumor progression under the scheduled treatment protocol. To address these challenges, we synthesized the cytotoxic peptide (KLAKLAK)2 (named KLAK) conjugated amphiphilic poly(ß-thioester)s copolymers (H-P-K) composed of reactive oxygen species (ROS) sensitive backbones and hydrophilic polyethylene glycol (PEG) side chains. H-P-K could self-assemble into micelle-like nanoparticles by hydrophobic interaction with copolymer backbones as cores and PEG and KLAK as shells. The assembled polymer-peptide nanoparticles remarkably improved cellular internalization and accumulation of therapeutic KLAK in cells. Compared to free KLAK peptide, the antitumor activity of H-P-K was significantly enhanced up to ∼400 times, suggesting the effectiveness of the nanoscaled polymer-peptide conjugation as biopharmaceuticals. The higher antitumor activity of nanoparticles was attributed to the efficient disruption of mitochondrial membranes and subsequent excessive ROS production in cells. To realize the ROS monitoring and treatment evaluation, we encapsulated squaraine (SQ) dyes as built-in reporters in ROS-sensitive H-P-K micelles. The overgenerated ROS around mitochondria stimulated the swelling of nanoparticles and subsequent release of SQ, which formed H-aggregates and significantly increased the photoacoustic (PA) signal. We believed that this self-assembled polymer-peptide nanotherapeutics incorporating built-in reporters has great potential for high antitumor performance and in situ treatment evaluation.


Assuntos
Ciclobutanos/química , Neoplasias/tratamento farmacológico , Fragmentos de Peptídeos/uso terapêutico , Fenóis/química , Polímeros/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo , Apoptose/efeitos dos fármacos , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Humanos , Micelas , Nanopartículas/administração & dosagem , Nanopartículas/química , Estresse Oxidativo/efeitos dos fármacos , Fragmentos de Peptídeos/química , Polietilenoglicóis/química , Polímeros/química , Resultado do Tratamento
14.
Mol Pharm ; 12(8): 2869-78, 2015 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-26101892

RESUMO

Various nanomaterials have been demonstrated as autophagy inducers owing to their endocytosis cell uptake pathway and impairment of lysosomes. pH-dependent nanomaterials as drug delivery systems that are capable of dissociating in weakly acidic lysosomal environment (pH 4-5) and consequently releasing the payloads into the cytoplasm have been paid extensive attention, but their autophagy-modulating effects are less reported so far. In this study, we report pH-sensitive micelle-like nanoparticles (NPs) that self-assembled from poly(ß-amino ester)s to induce cell autophagy. By encapsulation of gold(I) compounds (Au(I)) into hydrophobic domains of NPs, the resultant Au(I)-loaded NPs (Au(I)⊂NPs) shows synergistic cancer cell killing performance. The Au(I)⊂NPs enter cells through endocytosis pathway and accumulate into acidic lysosomes. Subsequently, the protonation of tertiary amines of poly(ß-amino ester)s triggers the dissociation of micelles, damages the lysosomes, and blocks formation of autolysosomes from fusion of lysosomes with autophagosomes. In addition, Au(I) preferentially inhibits thioredoxin reductase (TrxR) in MCF-7 human breast cancer cells that directly links to up-regulate reactive oxygen species (ROS) and consequently induce autophagy and apoptosis. The blockade of autophagy leads to excessive depletion of cellular organelles and essential proteins and ultimately results in cell death. Therefore, pH-sensitive polymeric nanoparticles with gold(I) compound payloads can synergistically induce cancer cell death through regulation of autophagy. Identification of the pH-sensitive nanomaterials for synergistically inducing cell death through regulation autophagy may open a new avenue for cancer therapy.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Ouro/química , Nanopartículas Metálicas/química , Polímeros/química , Linhagem Celular Tumoral , Portadores de Fármacos/química , Humanos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Lisossomos/metabolismo , Células MCF-7 , Micelas , Fagossomos/metabolismo , Espécies Reativas de Oxigênio/metabolismo
15.
Nanotechnology ; 26(35): 355703, 2015 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-26245834

RESUMO

Supramolecular self-assemblies with various nanostructures in organic and aqueous solutions have been prepared with desired functions. However, in situ construction of self-assembled superstructures in physiological conditions to achieve expected biological functions remains a challenge. Here, we report a supramolecular system to realize the in situ formation of nanoaggregates in living cells. The bis(pyrene) monomers were dispersed inside of hydrophobic domains of pH-sensitive polymeric micelles and delivered to the lysosomes of cells. In the acidic lysosomes, the bis(pyrene) monomers were released and self-aggregated with turn-on fluorescence. We envision this strategy for in situ construction of supramolecular nanostructures in living cells will pave the way for molecular diagnostics in the future.


Assuntos
Técnicas Citológicas/métodos , Corantes Fluorescentes/química , Nanoestruturas/química , Polímeros/química , Pirenos/química , Corantes Fluorescentes/metabolismo , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Polímeros/metabolismo , Pirenos/metabolismo
16.
Bioconjug Chem ; 25(11): 2021-9, 2014 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-25370305

RESUMO

For the purpose of near-infrared (NIR) fluorescence and photoacoustic (PA) tomography dual-modular imaging, self-assembly of squaraine (SQ) dyes is constructed in the hydrophobic phospholipid bilayers of liposomes (SQ⊂L) with variable mixing ratios of SQ and phospholipids from 1:500 to 1:10 (w/w). When doping minimal amounts of SQ, molecularly dispersed SQ in bilayers shows remarkable fluorescence. Interesting, the PA signal is enhanced with increase of SQ in the nanoconfined bilayer region, which is attributed to the formation of SQ-based H-aggregates and enhanced thermal conversion efficiency (η). SQ⊂L shows satisfactory chemical and thermal stabilities and photobleaching resistance. SQ⊂L is well-distributed in the cytoplasm of MCF-7 cells and its fluorescence signal remains for 7 days without dramatic quenching owing to the good stability of SQ⊂L. Furthermore, SQ⊂L is subjected to in vivo NIR fluorescence imaging to evaluate the whole-body biodistribution in organ level. Particularly, PA imaging with deeper tissue penetration capability is utilized to investigate the heterogeneous distribution SQ⊂L inside solid tumor. The majority of SQ⊂L are enriched in the area where the blood vessels are generated, implying that the liposomal nanocarriers exhibit lower tumor tissue penetration capability after the vascular leakage. This result is validated by histological examination of tumor tissue in parallel.


Assuntos
Ciclobutanos/química , Raios Infravermelhos , Nanoestruturas , Imagem Óptica/métodos , Fenóis/química , Técnicas Fotoacústicas/métodos , Animais , Ciclobutanos/farmacocinética , Feminino , Corantes Fluorescentes/química , Corantes Fluorescentes/farmacocinética , Humanos , Interações Hidrofóbicas e Hidrofílicas , Imageamento Tridimensional , Lipossomos , Células MCF-7 , Neoplasias Mamárias Experimentais/diagnóstico , Camundongos , Modelos Moleculares , Conformação Molecular , Fenômenos Ópticos , Fenóis/farmacocinética , Fosfolipídeos/química
17.
Biomacromolecules ; 14(5): 1555-63, 2013 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-23570500

RESUMO

A series of well-defined thermoresponsive diblock copolymers (PEO45-b-PtNEAn, n=22, 44, 63, 91, 172) were prepared by the atom transfer radical polymerization of trans-N-(2-ethoxy-1,3-dioxan-5-yl) acrylamide (tNEA) using a poly(ethylene oxide) (PEO45) macroinitiator. All copolymers are water-soluble at low temperature, but upon quickly heating to 37 °C, laser light scattering (LLS) and transmission electron microscopy (TEM) characterizations indicate that these copolymers self-assemble into aggregates with different morphologies depending on the chain length of PtNEA and the polymer concentration; the morphologies gradually evolved from spherical solid nanoparticles to a polymersome as the degree of polymerization ("n") of PtNEA block increased from 22 to 172, with the formation of clusters with rod-like structure at the intermediate PtNEA length. Both the spherical nanoparticle and the polymersome are stable at physiological pH but susceptible to the mildly acidic medium. Acid-triggered hydrolysis behaviors of the aggregates were investigated by LLS, Nile red fluorescence, TEM, and (1)H NMR spectroscopy. The results revealed that the spherical nanoparticles formed from PEO45-b-PtNEA44 dissociated faster than the polymersomes of PEO45-b-PtNEA172, and both aggregates showed an enhanced hydrolysis under acidic conditions. Both the spherical nanoparticle and polymersome are able to efficiently load the hydrophobic doxorubicin (DOX), and water-soluble fluorescein isothiocyanate-lysozyme (FITC-Lys) can be conveniently encapsulated into the polymersome without using any organic solvent. Moreover, FITC-Lys and DOX could be coloaded in the polymersome. The drugs loaded either in the polymersome or in the spherical nanoparticle could be released by acid triggering. Finally, the DOX-loaded assemblies display concentration-dependent cytotoxicity to HepG2 cells, while the copolymers themselves are nontoxic.


Assuntos
Resinas Acrílicas/síntese química , Portadores de Fármacos/síntese química , Nanopartículas/química , Polímeros/síntese química , Resinas Acrílicas/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/farmacologia , Portadores de Fármacos/farmacologia , Composição de Medicamentos , Fluoresceína-5-Isotiocianato , Células Hep G2 , Humanos , Concentração de Íons de Hidrogênio , Hidrólise , Interações Hidrofóbicas e Hidrofílicas , Micelas , Microscopia Eletrônica de Transmissão , Muramidase , Nanopartículas/ultraestrutura , Tamanho da Partícula , Polimerização , Polímeros/farmacologia , Solubilidade , Temperatura
18.
Int J Surg Pathol ; : 10668969231189172, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37545350

RESUMO

Rhabdomyosarcoma (RMS) with TFCP2 rearrangement has been identified recently. This entity has a distinctive clinicopathologic features: a rapidly aggressive clinical course, a preference for the craniofacial bones, a spindle and epithelioid histomorphology, and positive immunohistochemistry for epithelial markers, ALK, and myogenic markers. RMS with TFCP2 rearrangement is rare and may be misdiagnosed as other spindle cell tumors. Here, we report a case of this entity arising in the mandible, which was initially diagnosed as ossifying fibroma in primary tumor in another hospital. A 26-year-old man presented with a recurred mass in the mandible for 1 month after the operation of mandibular tumor. The first excisional specimen was initially diagnosed as ossifying fibroma in another hospital. Histopathologic examination revealed the tumor with a hybrid spindle cell and epithelioid cytomorphology, spindle cells and spindle-to-epithelioid cells with eosinophilic and rich cytoplasm, with high-grade features, prominent nucleoli and some atypical mitosis. Immunohistochemical analysis revealed positivity for desmin, MYOD1, pan-keratin, ALK (5A4), ALK (D5F3). Based on the morphology and immunophenotype, molecular studies were performed, which revealed a FUS::TFCP2 fusion transcript, confirming the diagnosis of Rhabdomyosarcoma with FUS::TFCP2 fusion. Making a correct diagnosis is primarily dependent on awareness by the pathologist of this rare subtype of RMS and careful histopathological evaluation, supported by immunohistochemical and molecular analysis, to avoid potential diagnostic pitfalls.

19.
Biosens Bioelectron ; 223: 115027, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36580815

RESUMO

In order to improve the recognition performance of MIPs sensors in chiral drug enantiomers, a novel a highly selective molecular recognition method based on protein-assisted immobilization of chiral molecular conformation was developed. S-fluoxetine (S-FLX) as the target chiral molecule, human serum albumin (HSA), which has a high affinity and strong interactions with S-FLX, was screened from 11 proteins to serve as an auxiliary recognition unit for the fixation of chiral conformation. By incorporating HSA into the preparation of molecularly imprinted polymers (MIPs), the natural chirality and high stereoselectivity of the protein were leveraged for the induction and fixation of the stereo conformation of S-FLX, refinement of internal structures of the imprinted cavities. The sensor exhibited excellent chiral recognition ability and high detection sensitivity. The changes of probe signal intensity of the MIPs/HSA sensor were positively correlated with the logarithmic concentration of S-FLX in the range of 1.0 × 10-16-1.0 × 10-11 mol L-1, where a detection limit of 6.43 × 10-17 mol L-1 was achieved (DL = 3δb/K). The selectivity of MIPs/HSA sensor in recognizing S-FLX was increased by 18.5 times and the sensitivity was increased by 2.6 times after the incorporation of HSA. The developed sensor was successfully used for the analysis of S-FLX in fluoxetine hydrochloride capsules.


Assuntos
Técnicas Biossensoriais , Impressão Molecular , Humanos , Fluoxetina/análise , Fluoxetina/química , Fluoxetina/metabolismo , Impressão Molecular/métodos , Albumina Sérica Humana , Proteínas , Polímeros Molecularmente Impressos
20.
Huan Jing Ke Xue ; 44(4): 2122-2135, 2023 Apr 08.
Artigo em Zh | MEDLINE | ID: mdl-37040962

RESUMO

Microplastics are widely distributed in the marine environment and are harmful to the health of marine organisms (including corals). However, studies on the impact of microplastics on coral have been very limited, and the specific mechanism of their impact is not clear. Therefore, in this study, microplastic PA, which is common in the marine environment, was selected to conduct a 7-day microplastic exposure experiment on Sinularia microclavata. The effects of microplastic exposure at different times on the diversity, community structure, and function of the symbiotic bacterial community of coral were analyzed using high-throughput sequencing technology. The α-diversity of the symbiotic bacterial community of coral first decreased and then increased with the exposure time of microplastics. The analysis of ß-diversity and microbial community composition showed that microplastic exposure caused significant changes in the symbiotic bacterial community of coral, and the bacterial community composition also changed with the exposure time. A total of 49 phyla, 152 classes, 363 orders, 634 families, and 1390 genera were detected. At the phylum level, Proteobacteria was the dominant taxa in all samples, but the relative abundance varied among samples. Microplastic exposure increased the abundance of Proteobacteria, Chloroflexi, Firmicutes, Actinobacteriota, Bacteroidota, and Acidobacteriota. At the genus level, Ralstonia, Acinetobacter, and Delftia were the dominant taxa of symbiotic bacteria of coral after microplastic exposure. PICRUSt functional prediction indicated that functions of the coral symbiotic bacterial community, including signal transduction, cellular community prokaryotes, xenobiotics biodegradation and metabolism, and cell motility, decreased after microplastic exposure on coral. BugBase phenotype predictions indicated that microplastic exposure altered three phenotypes (pathogenic, anaerobic, and oxidative stress-tolerant) of the coral symbiotic bacterial community. FAPROTAX functional predictions indicated that microplastic exposure caused significant changes in functions such as the symbiotic relationship between coral symbiotic bacteria and the host, carbon and nitrogen cycling, and photosynthesis. This study provided basic data on the mechanism of microplastic impacts on corals and microplastics ecotoxicology.


Assuntos
Antozoários , Microbiota , Animais , Microplásticos/análise , Plásticos , Antozoários/microbiologia , Antozoários/fisiologia , Bactérias , Proteobactérias
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