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1.
Research (Wash D C) ; 6: 0223, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37680304

RESUMO

Photodynamic therapy with reactive oxygen species production is a prospective treatment to combat cancer stem cells (CSCs). However, the innate drawbacks, including short lifetime and diffusion distance of reactive oxygen species and hypoxia within solid tumors, have become bottlenecks for clinical applications of photodynamic therapy. Here, we develop a mitochondria-targeting hemicyanine-oleic acid conjugate (CyOA), which can self-assemble into supramolecular nanoparticles (NPs) without any exogenous excipients. CyOA is also shown for targeting the mitochondrial complex II protein succinate dehydrogenase to inhibit oxidative phosphorylation and reverse tumor hypoxia, resulting in 50.4-fold higher phototoxicity against breast cancer stem cells (BCSCs) compared to SO3-CyOA NPs that cannot target to mitochondria. In 4T1 and BCSC tumor models, CyOA NPs achieve higher tumor inhibition and less lung metastasis nodules compared to the clinically used photosensitizer Hiporfin. This study develops a self-assembled small molecule that can serve as both oxidative phosphorylation inhibitor and photosensitizer for eradication of CSCs and treatment of solid tumors.

2.
Pharmacol Res ; 190: 106740, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36958408

RESUMO

Cancer stem cells (CSCs) have been blamed as the main culprit of tumor initiation, progression, metastasis, chemoresistance, and recurrence. However, few anti-CSCs agents have achieved clinical success so far. Here we report a novel derivative of lonidamine (LND), namely HYL001, which selectively and potently inhibits CSCs by targeting mitochondria, with 380-fold and 340-fold lower IC50 values against breast cancer stem cells (BCSCs) and hepatocellular carcinoma stem cells (HCSCs), respectively, compared to LND. Mechanistically, we reveal that HYL001 downregulates glutaminase (GLS) expression to block glutamine metabolism, blunt tricarboxylic acid cycle, and amplify mitochondrial oxidative stress, leading to apoptotic cell death. Therefore, HYL001 displays significant antitumor activity in vivo, both as a single agent and combined with paclitaxel. Furthermore, HYL001 represses CSCs of fresh tumor tissues derived from liver cancer patients. This study provides critical implications for CSCs biology and development of potent anti-CSCs drugs.


Assuntos
Antineoplásicos , Neoplasias Hepáticas , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Antineoplásicos/metabolismo , Glutamina/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Mitocôndrias/metabolismo , Células-Tronco Neoplásicas , Linhagem Celular Tumoral
3.
Int J Biol Macromol ; 241: 124102, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-36958445

RESUMO

It is one of the most emergent challenges to prepare wound dressings for quickly and effectively controlling profuse bleeding in clinical surgery and emergent accident. In this work, a novel strategy has been developed to prepare methacrylated gelatin-dopamine (GelMA-DA)/quaternized chitosan (QCS)/glycerol (Gly) composite sponges with good biocompatibility, tissue self-adhesion, antibacterial activity, and hemostatic ability. Results show that the GelMA-DA/QCS/Gly sponges display good biocompatibility and water absorption capacity. The lap shear strength of the GelMA-DA/QCS/Gly sponge with the GelMA-DA content of 5 W/V% is approximately 128.36 ± 8.45, 125.17 ± 7.18, 138.29 ± 7.94, and 113.83 ± 9.28 kPa for skin, liver, muscle, and fat, respectively. The GelMA-DA/QCS/Gly sponge displays better antibacterial activity against Gram positive and negative bacteria than the commercial Gelatin hemostatic sponge and CS hemostatic sponge. Animal experiments using rat tail and liver bleeding model show that the hemostasis time and blood loss in the GelMA-DA/QCS/Gly sponge group is approximately 33.3 ± 6.7 s and 0.19 ± 0.05 g, respectively, which is also better than that of the commercial Gelatin hemostatic sponge and CS hemostatic sponge. These results demonstrate promising potential of the GelMA-DA/QCS/Gly sponges for applications as hemostatic wound dressings in clinical surgery and emergent treatment.


Assuntos
Quitosana , Hemostáticos , Ratos , Animais , Hemostáticos/farmacologia , Quitosana/farmacologia , Gelatina/farmacologia , Glicerol/farmacologia , Dopamina/farmacologia , Hemostasia , Hemorragia/tratamento farmacológico , Bandagens , Antibacterianos/farmacologia
4.
RSC Adv ; 12(36): 23637-23643, 2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-36090414

RESUMO

A nature-inspired strategy has been developed to prepare polyvinyl alcohol (PVA)/catechol-modified quaternized chitosan (QCS-C)/MXene hydrogels with good self-adhesion, frost-resistance, and high ion-conductivity. The PVA/QCS-C/MXene hydrogel shows an ionic conductivity of 8.82 S m-1 and a gauge factor of 33.53 at low strain (0-10%), and remains flexible and conductive at -47 °C. The PVA/QCS-C15/MXene hydrogel displays promising potential as an ionically conductive hydrogel sensor for applications in flexible electronic devices.

5.
J Mech Behav Biomed Mater ; 124: 104811, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34500354

RESUMO

The control of interfacial interaction between polymers and fillers is essential for the fabrication of high-performance polymer composites. In this work, poly(ether-ether-ketone)/silica (PEEK/SiO2) and PEEK/SiO2/graphene oxide (GO) composite were prepared by ball milling-ultrasonic dispersion combined with melt extrusion injection molding. GO nanosheets were introduced as the interfacial enhancer to improve interfacial binding between SiO2 and PEEK. Mechanical tests showed that the incorporation of SiO2 and GO greatly optimized the modulus, strength, and fracture toughness of the composites. The tensile strength and Young's modulus of the PEEK/SiO2 composites increases with the increase of SiO2 content. The maximum tensile strength and Young's modulus of the PEEK/SiO2 composites are approximate 95.9 ± 0.6 MPa and 4.007 ± 0.005 GPa at 30 wt% of SiO2, an increase of 6.4% and 21.2% than that of pure PEEK. The maximum tensile strength and Young's modulus of the PEEK/SiO2/GO composite are further improved to approximate 101.5 ± 0.7 MPa and 4.62 ± 0.08 GPa at a GO content of 1.5% wt, which is 12.6% and 39.4% higher than that of pure PEEK. In addition, SEM images show that numerous HA formed on the surface of the PEEK/SiO2/GO composite after immersion in SBF for 7 days, and the HA layer becomes gradually thicker after 14 days, implying the good osteogenic activity of PEEK/SiO2/GO composites. Therefore, these results suggest that the use of GO as a novel filler surface modifier for the preparation of high-performance composites may become a novel interfacial design strategy for the development of high-performance composites.


Assuntos
Cetonas , Dióxido de Silício , Éter , Éteres , Grafite , Polietilenoglicóis
6.
Acta Biomater ; 131: 532-543, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34245893

RESUMO

Magnetic resonance imaging (MRI) has attracted increasing attention as a feasible alternative or adjunctive imaging modality for X-ray digital subtraction angiography because of the high tissue resolution and non-ionization radiation. In this study, a one-step electrospray method was developed to fabricate PVA microspheres encapsulated with in situ synthesized Fe3O4 nanoparticles. Fe3O4@PVA microspheres were mono-dispersed black spheres with a wide range of sizes (262-958 µm). The in situ-synthesized Fe3O4 nanoparticles were used as the contrast agent of MRI and the cross-linkers of PVA matrixes for the embolization purpose. In vivo evaluation of renal arteries of normal rabbits showed that Fe3O4@PVA microspheres had good embolic effect and enhanced capability of MRI. In vitro and in vivo biosafety assessment confirmed that Fe3O4@PVA microspheres had favorable biocompatibility. The DOX-loaded Fe3O4@PVA microspheres showed a typical drug-sustained release profile. These results suggest that the prepared DOX-loaded Fe3O4@PVA microspheres have the function of MRI, embolotherapy and chemotherapy. We expect our study could provide a simple and useful approach for the systematic design, fabrication, and application of a new type of magnetic microspheres as a triple-functional embolic agent for the development of MRI-guided TACE. STATEMENT OF SIGNIFICANCE: Due to the low tissue resolution and hazardous ionization radiation of X-ray digital subtraction angiography, it is beneficial to study MR imaging embolic microspheres for the development of MRI-guided TACE. In this study, a one-step electrospray method was firstly developed to fabricate PVA microspheres encapsulated with in situ synthesized Fe3O4 nanoparticles. Then, chemotherapeutic agent (DOX), contrast media of MRI (Fe3O4) and embolic agent (PVA matrix) were combined together in one body (DOX-loaded Fe3O4@PVA microspheres) to achieve the triple effects of chemotherapy, MR imaging and embolization. This triple-functional embolic agent offers potential for the future development of MRI-guided TACE.


Assuntos
Embolização Terapêutica , Nanopartículas , Animais , Meios de Contraste , Imageamento por Ressonância Magnética , Microesferas , Coelhos
7.
RSC Adv ; 11(9): 4883-4889, 2021 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-35424435

RESUMO

Zero-valent iron nanoparticles (ZVI NPs) display promising potential in the removal of organic pollutants and heavy metal ions for environmental remediation. However, it is crucial to prevent the oxidation of ZVI NP and control the release of Fe ions under storage and working conditions. In this study, ZVI NPs are encapsulated in single-axial and co-axial carbon nanofibers by electrospinning polyacrylonitrile (PAN)/Fe3+ nanofibrous mats with different structures and then annealing the PAN nanofibrous mats in reduction atmosphere. SEM images show that the diameter of the carbon nanofibers is affected by the structure of the nanofibers and the ZVI NPs content after the annealing treatment. The formation of ZVI NPs is confirmed through XPS spectra and HRTEM characterization. The catalytic degradation of organic pollutants by ZVI NPs encapsulated in the carbon nanofibrous mats is evaluated using methylene blue (MB). The results show that the degradation rate of MB is significantly improved when the ZVI NP content encapsulated in the nanofibers increased. MB is completely degraded by the nanofibrous mats with either the single-axial structure or the co-axial structure, but at a higher degradation rate by the single-axial structure than that by the co-axial structure. These results provide alternatives to utilize the carbon nanofibrous mats encapsulating ZVI NPs as Fe reservoir for the removal of organic pollutants in an emergent or long-term situation for environmental remediation.

8.
ACS Omega ; 5(45): 29398-29406, 2020 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-33225171

RESUMO

Poly(ether-ether-ketone) (PEEK) displays promising potential in hard tissue repair and orthopedic surgery due to its adaptable mechanical performance, good chemical resistance, and bioinertness. However, the low biointerfacial affinity of pure PEEK implants and the decrease of mechanical strength after processing greatly limit their clinical applications. In this work, the influences on mechanical performance and biointerfacial affinity of the PEEK/nanohydroxyapatite (nHA) composites are systematically investigated. Results show that the mechanical performance of PEEK/nHA composites was improved by adjusting the nHA content. The maximum values of the tensile, compressive, bending, and impact strength of the composites were increased by approximately 16.2, 25, 54, and 21%, respectively, when compared with that of pure PEEK. Studies in vitro show that PEEK/nHA composites display good cytocompatibility and promote the biomimic formation of HA, adhesion, and proliferation of L929 cells on the surface. Studies in vivo demonstrate that, compared to the pure PEEK, PEEK/nHA composites exhibit higher biointerfacial affinity, including the adhesion and encapsulation of muscle tissues on the surface of the implants and the suppression of inflammatory reaction around the implants. Our findings could pave the way for extensive applications of PEEK/nHA composites in hard tissue repair, particularly orthopedic surgery.

9.
Nanoscale ; 12(23): 12578-12588, 2020 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-32500910

RESUMO

Synergistic therapy with high efficacy and low side effects is of great significance in cancer treatment, and therefore the elaborate design of advanced nanocarriers to benefit diverse loading requirements of size-varied therapy agents is of critical importance. Herein, we demonstrate a multifunctional drug carrier platform based on a hierarchical porous and -NH2-modified silica nanocarrier (FMSN) with a super high specific surface area and a large pore volume, which not only improves the loading capacity of both doxorubicin, a chemotherapeutic drug, and black phosphorus quantum dots (BPQDs), a kind of biocompatible photothermal agent, but also enhances the photothermal stability and biostability of the degradable BPQDs. The unique structure and surface design enable our multimodal platform with heat-stimulative, pH-responsive and sustained-release properties for chemo-photothermal synergistic cancer therapy. Both cytotoxicity experiments and in vivo study reveal that the combined therapy based on our multifunctional nanohybrids mediates the highest death rate of cancer cells compared to that of single chemotherapy or photothermal therapy. Our hierarchical mesoporous strategy provides an excellent drug delivery model for advanced chemo-photothermal synergistic targeted cancer therapy.


Assuntos
Antineoplásicos , Hipertermia Induzida , Nanopartículas , Neoplasias , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Neoplasias/tratamento farmacológico , Fósforo , Fototerapia , Dióxido de Silício
10.
RSC Adv ; 10(41): 24397-24409, 2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-35516223

RESUMO

Advances in the tumor microenvironment have facilitated the development of novel anticancer drugs and delivery vehicles for improved therapeutic efficacy and decreased side effects. Disulfide bonds with unique chemical and biophysical properties can be used as cleavable linkers for the delivery of chemotherapeutic drugs. Accordingly, small molecule-, peptide-, polymer- and protein-based multifunctional prodrugs bearing cleavable disulfide bonds are well accepted in clinical settings. Herein, we first briefly introduce a number of prodrugs and divide them into three categories, namely, disulfide-containing small molecule conjugates, disulfide-containing cytotoxic agent-targeted fluorescent agent conjugates, and disulfide-containing cytotoxic agent-macromolecule conjugates. Then, we discuss the complex redox environment and the underlying mechanism of free drug release from disulfide based prodrugs in in vivo settings. Based on these insights, we analyze the impact of electronics, steric hindrance and substituent position of the disulfide linker on the extracellular stability and intracellular cleavage rate of disulfide containing prodrugs. Current challenges and future opportunities for the disulfide linker are provided at the end.

11.
J Agric Food Chem ; 68(3): 751-758, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31861959

RESUMO

The present study aimed to investigate the combined effects of defatted walnut meal hydrolysate (DWMH) and tea polyphenols (TP) on learning improvement and to explain mechanistically why the combined treatments were more effective than either subject alone. In the step-down avoidance test and the Morris water maze test, codelivery of DWMH and TP was more effective than either individual supplement in reversing memory impairment in scopolamine-treated mice. Mixing with TP significantly facilitated the protective effects of DWMH or DWMH-derived peptides (cationic peptide P1 and anionic peptide P2) on H2O2-injured SH-SY5Y cells. Although combination treatment with TP and DWMH did not significantly alter systemic exposure to P1 or P2 in rats, it significantly increased the accumulation of the two peptides in the mouse brain. In addition, TP significantly improved cellular uptake of P1 and P2 by brain capillary endothelial cells, indicating that TP enhanced the blood-brain barrier permeation of DWMH-derived peptides. The proposed explanation for the advantage of combined treatment with TP and DWMH in reversing memory impairment was that TP enhanced both the protective effects of DWMH on nerve cells and the accumulation of DWMH in the brain. Our study can aid efforts to develop products and investigate the effects of nutrient combinations on brain disorders.


Assuntos
Camellia sinensis/química , Juglans/química , Transtornos da Memória/tratamento farmacológico , Fármacos Neuroprotetores/administração & dosagem , Extratos Vegetais/administração & dosagem , Polifenóis/administração & dosagem , Animais , Encéfalo/efeitos dos fármacos , Humanos , Aprendizagem/efeitos dos fármacos , Masculino , Aprendizagem em Labirinto , Transtornos da Memória/induzido quimicamente , Transtornos da Memória/psicologia , Camundongos , Nozes/química , Ratos , Ratos Sprague-Dawley , Escopolamina/efeitos adversos
12.
Nano Lett ; 19(8): 5806-5817, 2019 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-31331172

RESUMO

Constructing a tumor microenvironment stimuli activatable theranostic nanoparticle with simple components and preparation procedures for multimodality imaging and therapy remains a major challenge for current theranostic systems. Here we report a novel and simple glutathione (GSH)-responsive turn-on theranostic nanoparticle for dual-modal imaging and combination therapy. The theranostic nanoparticle, DHP, consisting of a disulfide-bond-linked hydroxyethyl starch paclitaxel conjugate (HES-SS-PTX) and a near-infrared (NIR) cyanine fluorophore DiR, is prepared with a simple one-step dialysis method. As DiR is encapsulated within the hydrophobic core formed by HES-SS-PTX, the fluorescence of DiR is quenched by the aggregation-caused quenching (ACQ) effect. Nonetheless, once DHP is internalized by cancer cells, the disulfide bond of HES-SS-PTX can be cleaved by intracellular GSH, leading to the synchronized release of conjugated PTX and loaded DiR. The released PTX could exert its therapeutic effect, while DiR could adsorb onto nearby endosome/lysosome membranes and regain its fluorescence. Thus, DHP could monitor the release and therapeutic effect of PTX through the fluorescence recovery of DiR. Remarkably, DHP can also be used as an in vivo probe for both fluorescent and photoacoustic imaging and at the same time achieves potent antitumor efficacy through chemo-photothermal combination therapy. This study provides novel insights into designing clinically translatable turn-on theranostic systems.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Corantes Fluorescentes/uso terapêutico , Glutationa/metabolismo , Nanopartículas/uso terapêutico , Neoplasias/terapia , Paclitaxel/uso terapêutico , Animais , Linhagem Celular Tumoral , Terapia Combinada , Hipertermia Induzida , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias/diagnóstico por imagem , Neoplasias/metabolismo , Imagem Óptica , Técnicas Fotoacústicas , Fototerapia , Nanomedicina Teranóstica
13.
J Agric Food Chem ; 67(12): 3305-3312, 2019 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-30817142

RESUMO

The peptide components of defatted walnut ( Juglans regia L.) meal hydrolysate (DWMH) remain unclear, hindering the investigation of biological mechanisms and exploitation of bioactive peptides. The present study aims to identify the peptide composition of DWMH, followed by to evaluate in vitro antioxidant effects of selected peptides and investigate mechanisms of antioxidative effect. First, more than 1 000 peptides were identified by de novo sequencing in DWMH. Subsequently, a scoring method was established to select promising bioactive peptides by structure based screening. Eight brand new peptides were selected due to their highest scores in two different batches of DWMH. All of them showed potent in vitro antioxidant effects on H2O2-injured nerve cells. Four of them even possessed significantly stronger effects than DWMH, making the selected bioactive peptides useful for further research as new bioactive entities. Two mechanisms of hydroxyl radical scavenging and ROS reduction were involved in their antioxidative effects at different degrees. The results showed peptides possessing similar capacity of hydroxyl radical scavenging or ROS reduction may have significantly different in vitro antioxidative effects. Therefore, comprehensive consideration of different antioxidative mechanisms were suggested in selecting antioxidative peptides from DWMH.


Assuntos
Antioxidantes/química , Juglans/química , Peptídeos/farmacologia , Extratos Vegetais/farmacologia , Proteínas de Plantas/química , Antioxidantes/farmacologia , Linhagem Celular , Humanos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Nozes/química , Estresse Oxidativo/efeitos dos fármacos , Peptídeos/química , Extratos Vegetais/química , Hidrolisados de Proteína/química , Espécies Reativas de Oxigênio/metabolismo
14.
Nanoscale ; 10(22): 10514-10527, 2018 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-29799599

RESUMO

Herein, reduction-responsive disintegratable nanoclusters (NCs) were prepared as a novel nanovehicle for targeted drug delivery. The NCs, with a diameter of ∼170 nm, were self-assembled from hydrophobically modified and iRGD decorated hydroxyethyl starch (iRGD-HES-SS-C18). DOX was loaded into the NCs as a model drug. DOX@iRGD-HES-SS-C18 NCs can disintegrate into smaller ones and release DOX under reduction stimuli. Due to the ligand-receptor binding interactions between iRGD and integrin αV, DOX@iRGD-HES-SS-C18 NCs can specifically bind to the cell membranes of HepG-2 and 4T1 cells (integrin αV positive), resulting in enhanced cellular uptake as compared to DOX@HES-SS-C18 NCs. After cellular internalization, the NCs were transported to endosomes/lysosomes in which the reductive environment triggered the disintegration and DOX release. As a consequence, DOX@iRGD-HES-SS-C18 NCs exhibited an enhanced antitumor effect as compared to DOX@HES-SS-C18 NCs and free DOX, in an in vitro antitumor activity study. The reduction-responsive disintegratable NCs reported here were proved to be a safe and efficient nanoplatform, holding significant translation potential for tumor-targeted drug delivery.


Assuntos
Sistemas de Liberação de Medicamentos , Nanopartículas/química , Oligopeptídeos/química , Animais , Linhagem Celular Tumoral , Doxorrubicina/administração & dosagem , Células Hep G2 , Humanos , Derivados de Hidroxietil Amido/química , Camundongos , Estrutura Molecular
15.
RSC Adv ; 8(30): 16619-16625, 2018 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-35540537

RESUMO

Nanofiber membranes display promising potential in biomedical fields, especially as scaffolds for drug delivery and tissue engineering. The structures and components of nanofibers play crucial roles in improving the mechanical properties and drug-releasing performance of nanofiber membranes. In this work, poly(lactic acid) (PLA)/graphene oxide (GO) nanofiber membranes with different structures (single-axial and co-axial structure) were prepared by electrospinning. The morphologies, structures, and mechanical properties of the as-prepared nanofiber membranes were characterized and compared. Furthermore, the drug-releasing performance of the as-prepared nanofiber membranes with different structures was evaluated by using an organic dye (Rhodamine B, RhB) as a drug model. Results show that the addition of GO not only significantly improved the thermal stability and mechanical properties of the PLA nanofiber membranes, but also promoted the cumulative release and release rate of RhB from nanofiber membranes. At the same GO concentration, the nanofiber membrane with the co-axial structure displayed a higher tensile strength and Young's modulus, but exhibited a lower cumulative release and release rate. The formation of the co-axial structure is beneficial in suppressing the initial burst release of RhB from nanofiber membranes.

16.
ACS Appl Mater Interfaces ; 9(22): 19215-19230, 2017 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-28513132

RESUMO

Paclitaxel (PTX) is an effective antineoplastic agent and shows potent antitumor activity against a wide spectrum of cancers. Yet, the wide clinical use of PTX is limited by its poor aqueous solubility and the side effects associated with its current therapeutic formulation. To tackle these obstacles, we report, for the first time, α-amylase- and redox-responsive nanoparticles based on hydroxyethyl starch (HES) for the tumor-targeted delivery of PTX. PTX is conjugated onto HES by a redox-sensitive disulfide bond to form HES-SS-PTX, which was confirmed by results from NMR, high-performance liquid chromatography-mass spectrometry, and Fourier transform infrared spectrometry. The HES-SS-PTX conjugates assemble into stable and monodispersed nanoparticles (NPs), as characterized with Dynamic light scattering, transmission electron microscopy, and atomic force microscopy. In blood, α-amylase will degrade the HES shell and thus decrease the size of the HES-SS-PTX NPs, facilitating NP extravasation and penetration into the tumor. A pharmacokinetic study demonstrated that the HES-SS-PTX NPs have a longer half-life than that of the commercial PTX formulation (Taxol). As a consequence, HES-SS-PTX NPs accumulate more in the tumor compared with the extent of Taxol, as shown in an in vivo imaging study. Under reductive conditions, the HES-SS-PTX NPs could disassemble quickly as evidenced by their triggered collapse, burst drug release, and enhanced cytotoxicity against 4T1 tumor cells in the presence of a reducing agent. Collectively, the HES-SS-PTX NPs show improved in vivo antitumor efficacy (63.6 vs 52.4%) and reduced toxicity in 4T1 tumor-bearing mice compared with those of Taxol. These results highlight the advantages of HES-based α-amylase- and redox-responsive NPs, showing their great clinical translation potential for cancer chemotherapy.


Assuntos
Nanopartículas , Animais , Antineoplásicos Fitogênicos , Linhagem Celular Tumoral , Sobrevivência Celular , Sistemas de Liberação de Medicamentos , Camundongos , Oxirredução , Paclitaxel , alfa-Amilases
17.
Int J Nanomedicine ; 9: 1049-63, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24591827

RESUMO

After oral administration in rodents, triptolide (TP), a diterpenoid triepoxide compound, active as anti-inflammatory, immunosuppressive, anti-fertility, anti-cystogenesis, and anticancer agent, is rapidly absorbed into the blood circulation (from 5.0 to 19.5 minutes after dosing, depending on the rodent species) followed by a short elimination half-life (from about 20 minutes to less than 1 hour). Such significant and rapid fluctuations of TP in plasma likely contribute to its toxicity, which is characterized by injury to hepatic, renal, digestive, reproductive, and hematological systems. With the aim of prolonging drug release and improving its safety, TP-loaded nanostructured lipid carriers (TP-NLCs), composed of Compritol® 888 ATO (solid lipid) and Capryol™ 90 (liquid lipid), were developed using a microemulsion technique. The formulated TP-NLCs were also characterized and in vitro release was evaluated using the dialysis bag diffusion technique. In addition, the pharmacokinetics and toxicology profiles of TP-NLCs were compared to free TP and TP-loaded solid lipid nanoparticles (TP-SLNs; containing Compritol 888 ATO only). Results demonstrate that TP-NLCs had mean particle size of 231.8 nm, increased drug encapsulation with a 71.6% efficiency, and stable drug incorporation for over 1-month. TP-NLCs manifested a better in vitro sustained-release pattern compared to TP-SLNs. Furthermore, TP-NLCs prolonged mean residence time (MRT)0-t (P<0.001, P<0.001), delayed Tmax (P<0.01, P<0.05) and decreased Cmax (P<0.01, P<0.05) compared to free TP and TP-SLNs, respectively, which was associated with reduced subacute toxicity in male rats. In conclusion, our data suggest that TP-NLCs are superior to TP-SLNs and could be a promising oral delivery system for a safer use of TP.


Assuntos
Diterpenos/administração & dosagem , Diterpenos/farmacocinética , Nanoestruturas/administração & dosagem , Nanoestruturas/química , Fenantrenos/administração & dosagem , Fenantrenos/farmacocinética , Administração Oral , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/farmacocinética , Anti-Inflamatórios não Esteroides/toxicidade , Diterpenos/toxicidade , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Emulsões , Compostos de Epóxi/administração & dosagem , Compostos de Epóxi/farmacocinética , Compostos de Epóxi/toxicidade , Lipídeos/química , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Nanomedicina , Nanoestruturas/ultraestrutura , Fenantrenos/toxicidade , Ratos , Ratos Sprague-Dawley
18.
Molecules ; 18(11): 13340-56, 2013 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-24172242

RESUMO

Triptolide (TP) often causes adverse reactions in the gastrointestinal tract when it is administered orally. This study aimed to prepare and optimize triptolide-loaded solid lipid nanoparticles (TP-SLN) with reduced gastric irritation. The microemulsion technique was used to formulate TP-SLN employing a five-level central composite design (CCD) that was developed for exploring the optimum levels of three independent variables on particle size, encapsulation efficiency (EE) and drug loading (DL). Quadratic polynomial models were generated to predict and evaluate the three independent variables with respect to the three responses. The optimized TP-SLN was predicted to comprise fraction of lipid of 49.73%, surfactant to co-surfactant ratio of 3.25, and lipid to drug ratio of 55.27, which showed particle size of 179.8 ± 5.7 nm, EE of 56.5 ± 0.18% and DL of 1.02 ± 0.003% that were in good agreement with predicted values. In addition, the optimized nanoparticles manifested a sustained-release pattern in vitro and were stable during 3 h of incubation in simulated gastric fluids without significant size change and the majority (91%) of the drug was protected. Furthermore, the nanoparticles did not show obvious gastric irritation caused by oral administration of TP in rats.


Assuntos
Diterpenos/administração & dosagem , Diterpenos/efeitos adversos , Lipídeos/química , Nanopartículas/química , Fenantrenos/administração & dosagem , Fenantrenos/efeitos adversos , Animais , Diterpenos/química , Compostos de Epóxi/administração & dosagem , Compostos de Epóxi/efeitos adversos , Compostos de Epóxi/química , Mucosa Gástrica/efeitos dos fármacos , Lipídeos/administração & dosagem , Masculino , Nanopartículas/administração & dosagem , Fenantrenos/química , Ratos , Ratos Sprague-Dawley
19.
Biomaterials ; 34(36): 9124-33, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24008037

RESUMO

It is an emerging focus to explore a theranostic nanocarrier for simultaneous cancer imaging and therapy. Herein, we demonstrate a theranostic micelle system for cancer near infrared fluorescent (NIRF) imaging with enhanced signal to noise ratio and superior photothermal therapy. The copolymers consisting of monomethoxy poly(ethylene glycol) and alkylamine-grafted poly(L-aspartic acid) are assembled with carbocyanine dyes into theranostic micelles, which exhibit small size, high loading capacity, good stability, sustained release behavior, and enhanced cellular uptake. The micelles achieve the preferable biodistribution and long-term retention of carbocyanine dyes at tumor, which result in enhanced NIRF imaging by generating stable retention of NIRF signals at both hypervascular and hypovascular tumors during a long-term imaging period of up to 8 day, accompanying with negligible noise at normal tissues. The photostability of carbocyanine dye (Cypate) plays an important role for long-term cancer imaging with enhanced SNR. Moreover, the micelles exhibit severe photothermal damage on cancer cells via the destabilization of subcellular organelles upon photoirradiation, causing superior photothermal tumor regress. The micelles act as a powerful theranostic nanocarrier for simultaneous cancer imaging with high contrast and superior photothermal therapy.


Assuntos
Carbocianinas/farmacologia , Corantes/farmacologia , Hipertermia Induzida , Micelas , Neoplasias/diagnóstico , Fototerapia , Espectroscopia de Luz Próxima ao Infravermelho , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Diagnóstico por Imagem , Endocitose/efeitos dos fármacos , Feminino , Humanos , Verde de Indocianina/farmacologia , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Camundongos , Camundongos Nus , Neoplasias/patologia , Tamanho da Partícula , Distribuição Tecidual/efeitos dos fármacos
20.
Drug Dev Ind Pharm ; 39(1): 20-8, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23116283

RESUMO

OBJECTIVE: The objective of this work was to prepare coenzyme Q10 loaded nanostructured lipid carriers (Q10-NLC) and evaluate its epidermal targeting effect. METHODS: Q10-NLC was prepared by high-pressure microfluidics technique. Formulations and preparation parameters were optimized with response surface design. Q10-NLC was characterized by PCS, TEM, DSC and PXRD. The penetration of Q10 from the Q10-NLC formulations through skins and into skins were evaluated in vitro using Franz diffusion cells fitted with SD rat skins. In vitro release, long-term stability and light stability were also evaluated. RESULTS: The results showed that the concentration of solid lipid and emulsifier in formulation had a significant influence on particle size. The optimized preparation parameters were magnetic stirring for 20 min, high stirring at 8000 rpm for 1 min and high-pressure microfluidics at 1200 bar for three cycles. The size of Q10-NLC prepared by optimized formulation and parameters was (151.7 ± 2.31) nm, polydispersity (PDI) 0.144, ζ potential was (-44.1 ± 1.68) mV, drug loading 2.51%, encapsulation efficiency 100%. In vitro release study, Q10-NLC showed fast release during the first 3 hours and prolonged release afterwards. In vitro skin permeation study, the accumulative uptake of Q10 in epidermal of Q10-NLC was 10.11 times over Q10 emulsion. After exposure to day light for 24 hours, the amount of Q10 in Q10-NLC decreased only 5.59%, while in Q10 emulsion decreased 24.61% and Q10-ethanol solution 49.74%. CONCLUSION: Q10-NLC exhibited a significant epidermal targeting effect, which was proved to be a promising carrier for topical delivery of Q10.


Assuntos
Portadores de Fármacos , Nanopartículas/administração & dosagem , Ubiquinona/análogos & derivados , Administração Tópica , Animais , Epiderme , Lipídeos/administração & dosagem , Lipídeos/química , Microfluídica/métodos , Nanopartículas/química , Tamanho da Partícula , Ratos , Ratos Sprague-Dawley , Absorção Cutânea/efeitos dos fármacos , Ubiquinona/administração & dosagem , Ubiquinona/química
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