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1.
Arch Toxicol ; 95(1): 345-353, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32880718

RESUMO

Snakebite envenomation causes > 81,000 deaths and incapacities in another 400,000 people worldwide every year. Snake venoms are complex natural secretions comprised of hundreds of different molecules with a wide range of biological functions that after injection cause local and systemic manifestations. Although several studies have investigated snake venoms, the majority have focused on the protein portion (toxins), without significant attention paid to the lipid fraction. Therefore, an untargeted lipidomic approach based on liquid chromatography with high-resolution mass spectrometry (LC-HRMS) was applied to investigate the lipid constituents of venoms of the snake species Crotalus durissus terrificus and Bothrops moojeni. Phosphatidylcholines (PC), Lyso-PCs, phosphatidylethanolamines (PE), Lyso-PE, phosphatidylserine (PS), phosphatidylinositol (PI), ceramides (Cer), and sphingomyelin (SM) species were detected in the analyzed snake venoms. The identified lipids included bioactive compounds such as platelet-activating factor (PAF) precursor, PAF-like molecules, plasmalogens, ceramides, and sphingomyelins with long fatty acid chain lengths, which may be associated with the systemic responses triggered by C. d. terrificus and B. moojeni envenomation. These responses include platelet aggregation, activation of intercellular adhesion molecule 1 (ICAM1), apoptosis, as well as the production of pro-inflammatory lipid mediators, cytokines, and reactive species. The newly proposed lipidomics strategy provided valuable information regarding the lipid profiles of viperid venoms, which could lead to increased understanding of the complex pathology promoted by snakebite envenomation.


Assuntos
Bothrops , Ceramidas/metabolismo , Venenos de Crotalídeos/metabolismo , Crotalus , Lipidômica , Fosfolipídeos/metabolismo , Mordeduras de Serpentes , Esfingomielinas/metabolismo , Animais , Ceramidas/toxicidade , Cromatografia Líquida de Alta Pressão , Venenos de Crotalídeos/toxicidade , Fosfolipídeos/toxicidade , Esfingomielinas/toxicidade , Espectrometria de Massas em Tandem
2.
Small ; 16(27): e1906493, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32468702

RESUMO

Polymer-lipid hybrid vesicles are an emerging type of nano-assemblies that show potential as artificial organelles among others. Phospholipids and poly(cholesteryl methacrylate)-block-poly(methionine methacryloyloxyethyl ester (METMA)-random-2-carboxyethyl acrylate (CEA)) labeled with a Förster resonance energy transfer (FRET) reporter pair are used for the assembly of small and giant hybrid vesicles with homogenous distribution of both building blocks in the membrane as confirmed by the FRET effect. These hybrid vesicles have no inherent cytotoxicity when incubated with HepG2 cells up to 1.1 × 1011 hybrid vesicles per mL, and they are internalized by the cells. In contrast to the fluorescent signal originating from the block copolymer, the fluorescent signal coming from the lipids is barely detectable in cells incubated with hybrid vesicles for 6 h followed by 24 h in cell media, suggesting that the two building blocks have a different intracellular fate. These findings provide important insight into the design criteria of artificial organelles with potential structural integrity.


Assuntos
Fosfolipídeos , Polímeros , Sobrevivência Celular , Transferência Ressonante de Energia de Fluorescência , Células Hep G2 , Humanos , Fosfolipídeos/química , Fosfolipídeos/toxicidade , Polímeros/química , Polímeros/toxicidade , Vesículas Transportadoras/química
3.
ACS Appl Mater Interfaces ; 12(20): 23311-23322, 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32349481

RESUMO

Dendritic macromolecules are potential candidates for nanomedical application. Herein, glycogen, the natural hyperbranched polysaccharide with favorable biocompatibility, is explored as an effective drug vehicle for treating liver cancer. In this system, glycogen is oxidized and conjugated with cancer drugs through a disulfide link, followed by in situ loading of polypyrrole nanoparticles and then coated with functional phospholipids to form the desired system, Gly-ss-DOX@ppy@Lipid-RGD. The phospholipid layer has good cell affinity and can assist the system to penetrate into cells smoothly. Additionally, combined with the "fusion targeting" of glycogen and the active targeting effect of RGD toward liver cancer cells, Gly-ss-DOX@ppy@Lipid-RGD presents efficient specificity and enrichment of hepatocellular carcinoma. Owing to the glutathione-triggered cleavage of disulfide linkers, Gly-ss-DOX@ppy@Lipid-RGD can controllably release drugs to induce cell nucleus damage. Meanwhile, the polypyrrole nanoparticles can absorb near-infrared light and radiate heat energy within tumors. Besides enhancing drug release, the heat can also provide photothermal treatment for tumors. As proved by in vitro and in vivo experiments, Gly-ss-DOX@ppy@Lipid-RGD is a remarkable candidate for synergistic chemophotothermal therapy with high anticancer therapeutic activity and reduced systematic toxicity, efficiently suppressing tumor growth. All results demonstrate that glycogen nanoparticles are expected to be a new building block for accurate hepatocellular carcinoma treatment.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Doxorrubicina/uso terapêutico , Glicogênio/química , Neoplasias Hepáticas/tratamento farmacológico , Nanopartículas/química , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Terapia Combinada , Doxorrubicina/química , Doxorrubicina/farmacologia , Liberação Controlada de Fármacos , Glicogênio/toxicidade , Hemólise/efeitos dos fármacos , Humanos , Hipertermia Induzida/métodos , Raios Infravermelhos , Camundongos Endogâmicos BALB C , Nanopartículas/efeitos da radiação , Nanopartículas/toxicidade , Fosfolipídeos/química , Fosfolipídeos/toxicidade , Fotoquimioterapia , Polímeros/química , Polímeros/efeitos da radiação , Polímeros/toxicidade , Pirróis/química , Pirróis/efeitos da radiação , Pirróis/toxicidade
4.
Curr Drug Deliv ; 17(3): 229-245, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32039682

RESUMO

BACKGROUND: Owing to the rich anticancer properties of flavonoids, there is a need for their incorporation into drug delivery vehicles like nanomicelles for safe delivery of the drug into the brain tumor microenvironment. OBJECTIVE: This study, therefore, aimed to prepare the phospholipid-based Labrasol/Pluronic F68 modified nano micelles loaded with flavonoids (Nano-flavonoids) for the delivery of the drug to the target brain tumor. METHODS: Myricetin, quercetin and fisetin were selected as the initial drugs to evaluate the biodistribution and acute toxicity of the drug delivery vehicles in rats with implanted C6 glioma tumors after oral administration, while the uptake, retention, release in human intestinal Caco-2 cells and the effect on the brain endothelial barrier were investigated in Human Brain Microvascular Endothelial Cells (HBMECs). RESULTS: The results demonstrated that nano-flavonoids loaded with myricetin showed more evenly distributed targeting tissues and enhanced anti-tumor efficiency in vivo without significant cytotoxicity to Caco-2 cells and alteration in the Trans Epithelial Electric Resistance (TEER). There was no pathological evidence of renal, hepatic or other organs dysfunction after the administration of nanoflavonoids, which showed no significant influence on cytotoxicity to Caco-2 cells. CONCLUSION: In conclusion, Labrasol/F68-NMs loaded with MYR and quercetin could enhance antiglioma effect in vitro and in vivo, which may be better tools for medical therapy, while the pharmacokinetics and pharmacodynamics of nano-flavonoids may ensure optimal therapeutic benefits.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias Encefálicas/tratamento farmacológico , Portadores de Fármacos/administração & dosagem , Flavonoides/administração & dosagem , Glioma/tratamento farmacológico , Nanopartículas/administração & dosagem , Quercetina/administração & dosagem , Administração Oral , Animais , Antineoplásicos/farmacocinética , Antineoplásicos/toxicidade , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Linhagem Celular , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/toxicidade , Flavonoides/farmacocinética , Flavonoides/toxicidade , Flavonóis , Glioma/metabolismo , Glioma/patologia , Glicerídeos/administração & dosagem , Glicerídeos/farmacocinética , Glicerídeos/toxicidade , Humanos , Micelas , Nanopartículas/toxicidade , Fosfolipídeos/administração & dosagem , Fosfolipídeos/farmacocinética , Fosfolipídeos/toxicidade , Quercetina/farmacocinética , Quercetina/toxicidade , Ratos Sprague-Dawley , Distribuição Tecidual
5.
J Anesth ; 33(6): 628-635, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31473808

RESUMO

PURPOSE: Prolonged propofol infusion induces skeletal muscle damage. However, it is well known that the lipid emulsion that is the solvent of propofol causes various types of tissue damage via lipid peroxidation, and that propofol, conversely, has an anti-lipid peroxidative effect. The purpose of this study was to determine whether propofol or the lipid emulsion is the cause of muscle damage following prolonged administration. METHODS: Rats were divided into four groups: NI group (no intervention), Cath group (venous catheter insertion only), Prop group (1% propofol (Maruishi) intravenous infusion at 10 mg/kg/h), and Lipid group (10% Lipofundin® intravenous infusion at 100 mg/kg/h) (n = 10, each group). 1% Propofol (Maruishi) or Lipofundin was infused at 1 mL/kg/h for 72 h. The solvent of 1% propofol (Maruishi) is a 10% lipid emulsion. Lipofundin consists of 50% long-chain triacylglycerols and 50% medium-chain triacylglycerols, similar to the propofol solvent. Plasma concentrations of creatine kinase and myoglobin, superoxide production level, and 4-hydroxynonenal and malondialdehyde expression in the gastrocnemius muscle were evaluated 72 h after the interventions. RESULTS: Plasma concentrations of creatine kinase and myoglobin in the Lipid group were significantly higher than those in the other three groups. The superoxide production level, and 4-hydroxynonenal and malondialdehyde expression in the Lipid group were also significantly higher than in the other three groups. CONCLUSION: Lipofundin induces skeletal muscle damage via lipid peroxidation, and 1% propofol (Maruishi) conversely suppresses the muscle damage via antioxidant effects.


Assuntos
Peroxidação de Lipídeos/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Fosfolipídeos/toxicidade , Propofol/toxicidade , Sorbitol/toxicidade , Anestésicos Intravenosos/administração & dosagem , Animais , Antioxidantes/metabolismo , Combinação de Medicamentos , Infusões Intravenosas , Masculino , Malondialdeído/metabolismo , Propofol/administração & dosagem , Ratos , Ratos Wistar
6.
J Food Sci ; 84(9): 2572-2583, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31436862

RESUMO

This study was aimed to develop a novel nanocarrier for coenzyme Q10 (CoQ10) by a green process that prevented the use of surfactants and organic solvents. Triglyceride/phospholipid-based nanocarriers were developed through high-pressure homogenization (an industrial feasible process), and a 25-1 fractional factorial design was adopted to assess the influences of formulation variables on the considered responses, including vesicle size, entrapment efficiency, loading capacity, and solubility of the vehicles in simulated gastrointestinal fluids. The optimized formulation was further in-depth characterized in terms of morphology, release behavior, biocompatibility (Caco-2 cell cytotoxicity and histological examination), thermal behavior, and Fourier transform infrared analysis. Optimal nanocarriers were found to have mean particle size of 75 nm, narrow particle distribution, and CoQ10 entrapment of 95%. The optimized formulation was stable upon incubation in simulated gastrointestinal fluids without considerable leakage of cargo, which was in agreement with their sustained release behavior. Microscopic observations also confirmed nanosized nature of the vesicles and revealed their spherical shape. Moreover, toxicity evaluations at the cellular and tissue levels revealed their nontoxic nature. In conclusion, triglyceride/phospholipid-based nanocarriers proved to be a green safe vehicle for delivery of CoQ10 with industrial-scale production capability and could provide a new horizon for delivery of hydrophobic nutraceuticals. PRACTICAL APPLICATION: Green nanostructure formulation approaches have recently gained tremendous attraction for their safe profile especially when it comes to supplements, which are generally recommended for daily use. However, their sufficient association with cargoes and industrial-scale production have remained considerable challenges. This study focuses on the development of lipid-based nanocarriers for CoQ10 by an industrial feasible process that prevents the use of any surfactants or organic solvents.


Assuntos
Portadores de Fármacos , Nanoestruturas , Fosfolipídeos , Triglicerídeos , Ubiquinona/análogos & derivados , Células CACO-2 , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/química , Portadores de Fármacos/toxicidade , Química Verde , Humanos , Nanoestruturas/química , Nanoestruturas/toxicidade , Fosfolipídeos/química , Fosfolipídeos/toxicidade , Triglicerídeos/química , Triglicerídeos/toxicidade , Ubiquinona/química , Ubiquinona/farmacocinética
7.
Carbohydr Polym ; 214: 221-233, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30925992

RESUMO

This study has developed a versatile nano-system with the combined advantages of photothermal effect, active tumor-targeting, temperature-sensitive drug release, and photoacoustic imaging. The nano-system consists of the core of the phase change material (PCM), the outer polypyrrole (PPY) shell and the hyaluronic acid (HA) modified in the PPY shell. The obtained composite nanoparticles (denoted as DTX/PPN@PPY@HA) were spherical with a mean diameter of about 232.7 nm. In vivo and in vitro photoacoustic imaging experiments show that DTX/PPN@PPY@HA is an effective photoacoustic contrast agent, which can be used for accurate localization of tumor region and real-time guidance of photothermal chemotherapy. DTX/PPN@PPY@HA shows good photothermal effects and temperature-sensitive drug release. In addition, cellular experiments showed that DTX/PPN@PPY@HA could be efficiently internalized into tumor cells and produce significant cytotoxicity with the help of near-infrared (NIR) laser. Furthermore, the remarkable inhibition of DTX/PPN@PPY@HA against tumor growth was achieved in 4T1 tumor-bearing mice model.


Assuntos
Antineoplásicos/farmacologia , Meios de Contraste/química , Docetaxel/farmacologia , Portadores de Fármacos/química , Ácido Hialurônico/química , Nanopartículas/química , Animais , Antineoplásicos/administração & dosagem , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Meios de Contraste/administração & dosagem , Meios de Contraste/efeitos da radiação , Meios de Contraste/toxicidade , Docetaxel/administração & dosagem , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/efeitos da radiação , Portadores de Fármacos/toxicidade , Liberação Controlada de Fármacos , Feminino , Corantes Fluorescentes/química , Humanos , Ácido Hialurônico/administração & dosagem , Ácido Hialurônico/efeitos da radiação , Ácido Hialurônico/toxicidade , Raios Infravermelhos , Injeções Intravenosas , Pulmão/patologia , Neoplasias Pulmonares/prevenção & controle , Neoplasias Pulmonares/secundário , Camundongos Endogâmicos BALB C , Nanopartículas/administração & dosagem , Nanopartículas/efeitos da radiação , Nanopartículas/toxicidade , Tamanho da Partícula , Fosfolipídeos/administração & dosagem , Fosfolipídeos/química , Fosfolipídeos/efeitos da radiação , Fosfolipídeos/toxicidade , Técnicas Fotoacústicas/métodos , Polímeros/administração & dosagem , Polímeros/química , Polímeros/efeitos da radiação , Polímeros/toxicidade , Pirróis/administração & dosagem , Pirróis/química , Pirróis/efeitos da radiação , Pirróis/toxicidade , Temperatura , Nanomedicina Teranóstica/métodos
8.
Anal Chem ; 91(3): 2425-2430, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30620179

RESUMO

Exosomes (Exos) are nanoscale natural vehicles for transporting biomolecules to facilitate cell-to-cell communication, indicating a high potential of them for delivering therapeutics/diagnostics. To improve their delivery capacity, a simple, noninvasive, and efficient strategy for functionalizing Exos with effective targeting ligands as well as elucidation of the cellular uptake mechanism of these functionalized Exos was found be to necessary, but remained a challenge. In this work, we used diacyllipid-aptamer conjugates as the targeting ligand to develop an aptamer-functionalized Exos (Apt-Exos) nanoplatform for cell type-specific delivery of molecular therapeutics. The cellular uptake mechanism of Apt-Exos was investigated in details, and distinct behavior was observed in comparison to free Exos. By combining the excellent molecular recognition capability of aptamers and the superiority of Exos as natural vehicles, Apt-Exos can efficiently deliver molecular drugs/fluorophores to target cancer cells, providing a promising delivery platform for cancer theranostics.


Assuntos
Antineoplásicos/farmacologia , Aptâmeros de Nucleotídeos/química , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Exossomos/química , Aptâmeros de Nucleotídeos/metabolismo , Aptâmeros de Nucleotídeos/toxicidade , Linhagem Celular Tumoral , Portadores de Fármacos/metabolismo , Portadores de Fármacos/toxicidade , Liberação Controlada de Fármacos , Eletroporação , Endocitose/fisiologia , Exossomos/metabolismo , Humanos , Cinética , Fosfolipídeos/química , Fosfolipídeos/metabolismo , Fosfolipídeos/toxicidade , Estudo de Prova de Conceito
9.
Drug Deliv Transl Res ; 8(3): 617-632, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29637488

RESUMO

The current research work encompasses the development, characterization, and evaluation of self-assembled phospholipidic nano-mixed miceller system (SPNMS) of a poorly soluble BCS Class IV xanthone bioactive, mangiferin (Mgf) functionalized with co-delivery of vitamin E TPGS. Systematic optimization using I-optimal design yielded self-assembled phospholipidic nano-micelles with a particle size of < 60 nm and > 80% of drug release in 15 min. The cytotoxicity and cellular uptake studies performed using MCF-7 and MDA-MB-231 cell lines demonstrated greater kill and faster cellular uptake. The ex vivo intestinal permeability revealed higher lymphatic uptake, while in situ perfusion and in vivo pharmacokinetic studies indicated nearly 6.6- and 3.0-folds augmentation in permeability and bioavailability of Mgf. In a nutshell, vitamin E functionalized SPNMS of Mgf improved the biopharmaceutical performance of Mgf in rats for enhanced anticancer potency.


Assuntos
Micelas , Nanoestruturas/administração & dosagem , Fosfolipídeos/administração & dosagem , Vitamina E/administração & dosagem , Xantonas/administração & dosagem , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Feminino , Humanos , Jejuno/metabolismo , Nanoestruturas/química , Nanoestruturas/toxicidade , Fosfolipídeos/química , Fosfolipídeos/toxicidade , Ratos Sprague-Dawley , Solubilidade , Vitamina E/química , Vitamina E/toxicidade , Xantonas/química , Xantonas/toxicidade
10.
Biomaterials ; 105: 185-194, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27522253

RESUMO

Sustained antigen delivery using incomplete Freund's adjuvant (IFA) can induce strong, long-term immune response, but it can also cause severe side effects. Here we describe an injectable, phospholipid-based phase separation gel (PPSG) that readily transforms in situ into a drug depot. PPSG loaded with the model antigen ovalbumin (OVA) supported sustained OVA release in mice that lasted nearly one month. Immunizing mice with a single injection of PPSG/OVA elicited a strong and persistent increase in titers of OVA-specific IgG, IgG1 and IgG2a. Co-administering CpG-ODN further increased antibody titers. Such co-administration recruited dendritic cells to injection sites and activated dendritic cells in the draining lymph nodes. Moreover, immunization with PPSG/OVA/CpG resulted in potent memory antibody responses and high frequency of memory T cells. Remarkably, PPSG/OVA/CpG was associated with much lower toxicity at injection sites than IFA/OVA/CpG, and it showed no systemic toxicity such as to lymph nodes or spleen. These findings illustrate the potential of injectable PPSG for sustained, minimally toxic delivery of antigens and adjuvants.


Assuntos
Antígenos/administração & dosagem , Antígenos/imunologia , Preparações de Ação Retardada/administração & dosagem , Imunidade Inata/imunologia , Nanocápsulas/química , Fosfolipídeos/química , Vacinação/métodos , Adjuvantes Imunológicos/administração & dosagem , Animais , Autoanticorpos/imunologia , Preparações de Ação Retardada/toxicidade , Relação Dose-Resposta a Droga , Feminino , Imunidade Inata/efeitos dos fármacos , Injeções , Camundongos , Camundongos Endogâmicos C57BL , Nanocápsulas/administração & dosagem , Nanocápsulas/toxicidade , Transição de Fase , Fosfolipídeos/toxicidade
11.
Eur J Pharm Biopharm ; 107: 295-309, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27519828

RESUMO

Chimeric systems are mixed nanovectors composed by different in nature materials and exhibit new functionalities and properties. The particular chimeric nanovectors, formed by the co-assembly of low and high molecular weight amphiphiles, have the potential to be utilized as drug delivery platforms. We have utilized two lipids, l-α-phosphatidylcholine, hydrogenated (Soy)(HSPC) and 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), and a poly(oligoethylene glycol acrylate)-b-poly(lauryl acrylate) (POEGA-PLA) block copolymer, at different molar ratios, in aqueous media. Light scattering, differential scanning calorimetry (DSC) and imaging techniques (cryo-TEM, AFM) were employed in order to elucidate the structure and properties of the nanostructures, as well as the cooperativity between the components. DSC experiments showed considerable interaction of the block copolymer with the lipid bilayers and suggested an inhomogeneous distribution of the copolymer chains and lateral phase separation of the components. Vesicle formation was observed in most cases by cryo-TEM with a chimeric membrane exhibiting kinks, in accordance with DSC data. A series of biocompatibility experiments indicated good in vitro biological stability and low cytotoxicity in vivo of the novel nanocarriers. Finally, ibuprofen (IBU) was used as model drug in order to study the loading and the release properties of the prepared chimeric lipid/block copolymer vesicles.


Assuntos
Materiais Biocompatíveis , Nanoestruturas/química , Fosfolipídeos/química , Polímeros/química , Animais , Varredura Diferencial de Calorimetria , Células Cultivadas , Humanos , Técnicas In Vitro , Bicamadas Lipídicas/química , Camundongos , Camundongos Endogâmicos C57BL , Microscopia de Força Atômica , Microscopia Eletrônica de Transmissão , Fosfolipídeos/farmacocinética , Fosfolipídeos/toxicidade , Polímeros/farmacocinética , Polímeros/toxicidade
12.
J Control Release ; 220(Pt A): 295-307, 2015 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-26518724

RESUMO

The use of cationic lipids as gene delivery systems is a basic method in gene therapy. Through ongoing research, lipofection is currently the leader of non-viral vectors in clinical trials. However, in order to unleash the full potential of lipofection further intensive investigations are indispensable. In this study, various lipoplex formulations were compared regarding their ability to bind DNA. To obtain information about a possible premature release of DNA at the cell surface, heparin and chondroitin dependent lipoplex destabilization experiments were carried out. Complementary investigations in cell culture were performed to quantify DNA outside the cell. Additionally, DNase I stability was investigated. In this regard a multitude of methods, namely confocal laser scanning microscopy (CLSM), polymerase chain reaction (PCR), cell culture experiments, ethidium bromide assay, gel electrophoresis, Langmuir-isotherm experiments, infrared reflection absorption spectroscopy (IRRAS), Brewster angle microscopy (BAM), zeta-(ζ)-potential measurements, and dynamic light scattering (DLS), were applied. Although the complexation of DNA is a fundamental step, we show that the DNA release by biological agents (proteoglycans) and an unsuccessful cell attachment are major transfection limiting parameters.


Assuntos
DNA/metabolismo , Diamida/metabolismo , Malonatos/metabolismo , Fosfolipídeos/metabolismo , Transfecção/métodos , Animais , Sítios de Ligação , Cátions , Adesão Celular/efeitos dos fármacos , DNA/química , Desoxirribonuclease I/metabolismo , Diamida/análogos & derivados , Diamida/química , Diamida/toxicidade , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HeLa , Humanos , Células LLC-PK1 , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Malonatos/química , Malonatos/toxicidade , Conformação de Ácido Nucleico , Fosfolipídeos/química , Fosfolipídeos/toxicidade , Suínos , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia
13.
Anesth Analg ; 120(2): 329-40, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25437926

RESUMO

BACKGROUND: The IV anesthetic, propofol, when administered as fat emulsion-based formulation (Diprivan) promotes insulin resistance, but the direct effects of propofol and its solvent, Intralipid, on cardiac insulin resistance are unknown. METHODS: Hearts of healthy and type-2 diabetic rats (generated by fructose feeding) were aerobically perfused for 60 minutes with 10 µM propofol in the formulation of Diprivan or an equivalent concentration of its solvent Intralipid (25 µM) ± insulin (100 mU•L). Glucose uptake, glycolysis, and glycogen metabolism were measured using [H]glucose. Activation of Akt, GSK3ß, AMPK, ERK1/2, p38MAPK, S6K1, JNK, protein kinase Cθ (PKCθ), and protein kinase CCßII (PKCßII) was determined using immunoblotting. GLUT4 trafficking and phosphorylations of insulin receptor substrate-1 (IRS-1) at Ser307(h312), Ser1100(h1101), and Tyr608(hTyr612) were measured. Mass spectrometry was used to determine acylcarnitines, phospholipids, and sphingolipids. RESULTS: Diprivan and Intralipid reduced insulin-induced glucose uptake and redirected glucose to glycogen stores in diabetic hearts. Reduced glucose uptake was accompanied by lower GLUT4 trafficking to the sarcolemma. Diprivan and Intralipid inactivated GSK3ß but activated AMPK and ERK1/2 in diabetic hearts. Only Diprivan increased phosphorylation of Akt(Ser473/Thr308) and translocated PKCθ and PKCßII to the sarcolemma in healthy hearts, whereas it activated S6K1 and p38MAPK and translocated PKCßII in diabetic hearts. Furthermore, only Diprivan phosphorylated IRS-1 at Ser1100(h1101) in healthy and diabetic hearts. JNK expression, phosphorylation of Ser307(h312) of IRS-1, and PKCθ expression and translocation were increased, whereas GLUT4 expression was reduced in insulin-treated diabetic hearts. Phosphatidylglycerol, phosphatidylethanolamine, and C18-sphingolipids accumulated in Diprivan-perfused and Intralipid-perfused diabetic hearts. CONCLUSIONS: Propofol and Intralipid promote insulin resistance predominantly in type-2 diabetic hearts.


Assuntos
Anestésicos Intravenosos/toxicidade , Diabetes Mellitus Tipo 2/metabolismo , Emulsões Gordurosas Intravenosas/toxicidade , Transportador de Glucose Tipo 4/antagonistas & inibidores , Transportador de Glucose Tipo 4/metabolismo , Coração/efeitos dos fármacos , Resistência à Insulina , Fosfolipídeos/toxicidade , Propofol/toxicidade , Óleo de Soja/toxicidade , Animais , Citrato (si)-Sintase/metabolismo , Diabetes Mellitus Tipo 2/induzido quimicamente , Emulsões/toxicidade , Frutose , Glucose/metabolismo , Glicogênio/metabolismo , Glicólise/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-Dawley
14.
Int J Nanomedicine ; 9: 4867-78, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25364245

RESUMO

Layered double hydroxide (LDH) has attracted considerable attention as a drug carrier. However, because of its poor in vivo behavior, polyethylene glycolylated (PEGylated) phospholipid must be used as a coformer to produce self-assembled core-shell nanoparticles. In the present study, we prepared a PEGylated phospholipid-coated LDH (PLDH) (PEG-PLDH) delivery system. The PEG-PLDH nanoparticles had an average size of 133.2 nm. Their core-shell structure was confirmed by transmission electron microscopy and X-ray photoelectron spectroscopy. In vitro liposome-cell-association and cytotoxicity experiments demonstrated its ability to be internalized by cells. In vivo studies showed that PEGylated phospholipid membranes greatly reduced the blood clearance rate of LDH nanoparticles. PEG-PLDH nanoparticles demonstrated a good control of tumor growth and increased the survival rate of mice. These results suggest that PEG-PLDH nanoparticles can be a useful drug delivery system for cancer therapy.


Assuntos
Antineoplásicos/farmacologia , Antineoplásicos/farmacocinética , Portadores de Fármacos/química , Hidróxidos/química , Nanopartículas/química , Animais , Antineoplásicos/sangue , Antineoplásicos/química , Proteínas Sanguíneas/química , Peso Corporal/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/toxicidade , Células HeLa , Humanos , Hidróxidos/toxicidade , Metotrexato/sangue , Metotrexato/química , Metotrexato/farmacocinética , Metotrexato/farmacologia , Camundongos , Nanopartículas/toxicidade , Tamanho da Partícula , Fosfolipídeos/química , Fosfolipídeos/toxicidade , Polietilenoglicóis/química , Polietilenoglicóis/toxicidade , Ratos Sprague-Dawley , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Langmuir ; 30(39): 11704-13, 2014 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-25211646

RESUMO

Several experimental methods, such as zeta potential, gel electrophoresis, small-angle X-ray scattering, gene transfection, fluorescence microscopy, flow cytometry, and cell viability/cytotoxicity assays, have been used to analyze the potential of anionic lipids (AL) as effective nontoxic and nonviral DNA vectors, assisted by divalent cations. The lipoplexes studied are those comprised of the green fluorescent protein-encoding plasmid DNA pEGFP-C3, an anionic lipid as 1,2-dioleoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (DOPG) or 1,2-dioleoyl-sn-glycero-3-phospho-L-serine (DOPS), and a zwitterionic lipid, the 1,2-dioleoyl-sn -glycero-3-phosphatidylethanolamine (DOPE, not charged at physiological pH). The studies have been carried on at different liposome and lipoplex compositions and in the presence of a variety of [Ca2+]. Electrochemical experiments reveal that DOPG/DOPE and DOPS/DOPE anionic liposomes may compact more effectively pDNA at low molar fractions (with an excess of DOPE) and at AL/pDNA ratios ≈20. Calcium concentrations around 15-20 mM are needed to yield lipoplexes neutral or slightly positive. From a structural standpoint, DOPG/DOPE-Ca2+-pDNA lipoplexes are self-assembled into a HIIc phase (inverted cylindrical micelles in hexagonal ordering with plasmid supercoils inside the cylinders), while DOPS/DOPE-Ca2+-pDNA lipoplexes show two phases in coexistence: one classical HIIc phase which contains pDNA supercoils and one Lα phase without pDNA among the lamellae, i.e., a lamellar stack of lipidic bilayers held together by Ca2+ bridges. Transfection and cell viability studies were done with HEK293T and HeLa cells in the presence of serum. Lipoplexes herein studied show moderate-to-low transfection levels combined with moderate-to-high cell viability, comparable to those yield by Lipofectamine2000*, which is a cationic lipid (CL) standard formulation, but none of them improve the output of typical CL gen vectors, mostly if they are gemini or dendritic. This fact would be indicating that, nowadays, lipofection via anionic lipids and divalent cations as mediators still needs to enhance transfection levels in order to be considered as a real and plausible alternative to lipofection through improved CLs-based lipoplexes.


Assuntos
Cálcio/metabolismo , DNA/química , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Fosfolipídeos/química , Fosfolipídeos/metabolismo , Plasmídeos/genética , Sobrevivência Celular/efeitos dos fármacos , DNA/genética , Portadores de Fármacos/toxicidade , Eletroquímica , Terapia Genética , Células HEK293 , Células HeLa , Humanos , Lipossomos , Modelos Moleculares , Conformação Molecular , Fosfolipídeos/toxicidade , Transfecção
16.
Arch Biochem Biophys ; 548: 1-10, 2014 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-24607806

RESUMO

Electrophilic attack of hypochlorous acid on unsaturated bonds of fatty acyl chains is known to result mostly in chlorinated products that show cytotoxicity to some cell lines and were found in biological systems exposed to HOCl. This study aimed to investigate more deeply the products and the mechanism underlying cytotoxicity of phospholipid-HOCl oxidation products, synthesized by the reaction of HOCl with 1-stearoyl-2-oleoyl-, 1-stearoyl-2-linoleoyl-, and 1-stearoyl-2-arachidonyl-phosphatidylcholine. Phospholipid chlorohydrins were found to be the most abundant among obtained products. HOCl-modified lipids were cytotoxic towards HUVEC-ST (endothelial cells), leading to a decrease of mitochondrial potential and an increase in the number of apoptotic cells. These effects were accompanied by an increase of the level of active caspase-3 and caspase-7, while the caspase-3/-7 inhibitor Ac-DEVD-CHO dramatically decreased the number of apoptotic cells. Phospholipid-HOCl oxidation products were shown to affect cell proliferation by a concentration-dependent cell cycle arrest in the G0/G1 phase and activating redox sensitive p38 kinase. The redox imbalance observed in HUVEC-ST cells exposed to modified phosphatidylcholines was accompanied by an increase in ROS level, and a decrease in glutathione content and antioxidant capacity of cell extracts.


Assuntos
Cloridrinas/química , Cloridrinas/toxicidade , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Fosfolipídeos/química , Fosfolipídeos/toxicidade , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Caspase 7/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Ácido Hipocloroso/química , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Oxirredução/efeitos dos fármacos
17.
Ther Deliv ; 4(10): 1247-59, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24116910

RESUMO

BACKGROUND: Phospholipid and Tween(®) 80 mixed micelles were investigated as injectable nanocarriers for the natural anticancer compound, plumbagin (PBG), with the aim to improve anticancer efficiency. PBG-loaded mixed micelles were fabricated by self-assembly; composition being optimized using 3(2) factorial design. RESULTS & DISCUSSION: Optimized mixed micelles were spherical and 46 nm in size. Zeta potential, drug loading and encapsulation efficiency were 5.04 mV, 91.21 and 98.38% respectively. Micelles demonstrated sustained release of PBG. Micelles caused a 2.1-fold enhancement in vitro antitumor activity of PBG towards MCF-7 cells. Micelles proved safe for intravenous injection as PBG was stable at high pH; micelle size and encapsulation efficiency were retained upon dilution. CONCLUSION: Developed mixed micelles proved potential nanocarriers for PBG in cancer chemotherapy.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Mama/patologia , Portadores de Fármacos , Naftoquinonas/farmacologia , Fosfolipídeos/química , Polissorbatos/química , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/metabolismo , Antineoplásicos Fitogênicos/toxicidade , Proteínas Sanguíneas/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Química Farmacêutica , Preparações de Ação Retardada , Estabilidade de Medicamentos , Feminino , Hemólise/efeitos dos fármacos , Humanos , Cinética , Células MCF-7 , Micelas , Nanopartículas , Nanotecnologia , Naftoquinonas/administração & dosagem , Naftoquinonas/química , Naftoquinonas/metabolismo , Naftoquinonas/toxicidade , Tamanho da Partícula , Fosfolipídeos/metabolismo , Fosfolipídeos/toxicidade , Polissorbatos/metabolismo , Polissorbatos/toxicidade , Ligação Proteica , Solubilidade , Tecnologia Farmacêutica/métodos
18.
Int J Pharm ; 454(1): 472-7, 2013 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-23806812

RESUMO

In order to reduce the severe venous toxicity, we developed an intravenous lipid emulsion of vinorelbine and investigated its preclinical stability, toxicity and antitumor efficacy. Vinorelbine-phospholipid complex was prepared to enhance the lipophilicity of vinorelbine thus facilitating the encapsulation into lipid emulsion. After complexation more than 70% of vinorelbine was encapsulated into the oil phase. Meanwhile, the lipid emulsion showed good stability without drug leakage. Local irritation after injection of the lipid emulsion was investigated in rabbits and compared with Navelbine(®) (the commercial product). The antitumor therapeutic efficacies were evaluated in tumor-bearing mouse models inoculated with A549 human lung cancer cells and BCAP-37 human breast cancer cells and compared as well. Results showed that the lipid emulsion significantly reduced the injection irritation compared with that of Navelbine(®), while maintained the antitumor activity in A549 and BCAP-37 cells xenograft tumor mouse models. Taken together, lipid emulsion loaded with vinorelbine-phospholipid complex is a promising vinorelbine intravenous injection with reduced venous irritation.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Portadores de Fármacos , Emulsões Gordurosas Intravenosas/química , Neoplasias Pulmonares/tratamento farmacológico , Fosfolipídeos/química , Vimblastina/análogos & derivados , Administração Intravenosa , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/toxicidade , Neoplasias da Mama/patologia , Varredura Diferencial de Calorimetria , Linhagem Celular Tumoral , Química Farmacêutica , Cristalografia por Raios X , Estabilidade de Medicamentos , Emulsões Gordurosas Intravenosas/administração & dosagem , Emulsões Gordurosas Intravenosas/toxicidade , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Fosfolipídeos/administração & dosagem , Fosfolipídeos/toxicidade , Coelhos , Solubilidade , Tecnologia Farmacêutica/métodos , Veias/efeitos dos fármacos , Veias/patologia , Vimblastina/administração & dosagem , Vimblastina/química , Vimblastina/farmacologia , Vinorelbina , Ensaios Antitumorais Modelo de Xenoenxerto
19.
J Cardiovasc Pharmacol ; 61(2): 160-5, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23222311

RESUMO

Atherosclerosis is a major cause of death in the Western World. It is known that Lipofundin 20% induces atherosclerotic lesions, whereas ozone at low doses has been satisfactorily used in the prevention of oxidative stress-associated pathologies, such as coronary artery diseases. The aim of the present work was to evaluate the effects of ozone therapy on Lipofundin-induced atherosclerotic lesions in New Zealand White rabbits. Ozone (1 mg), mixed with oxygen as passive carrier, was administered by rectal insufflation during 15 sessions in 5 weeks. Then, the animals were intravenously treated with 2 mL/kg of Lipofundin, daily during 8 days. Animals were euthanized and eosin and hematoxylin staining was used for aortic histopathological analysis. The biomarkers of oxidative stress and lipid profile in serum were determined by spectrophotometric techniques. The results demonstrated that ozone induced inhibitory effects on aortic lesions formation. On the other hand, a reduction of biomolecular damage and an increase of antioxidant systems were observed at the end of the experiment. The serum lipids profiles were not modified after only 1 cycle of ozone treatment. Our results reinforced the hypotheses that antioxidant effects induced by ozone in the context of atherosclerosis demonstrate the antiatherogenic properties of the gas in the experimental conditions of this study.


Assuntos
Antioxidantes/farmacologia , Aterosclerose/prevenção & controle , Estresse Oxidativo/efeitos dos fármacos , Ozônio/farmacologia , Animais , Antioxidantes/administração & dosagem , Antioxidantes/metabolismo , Aorta/efeitos dos fármacos , Aorta/patologia , Modelos Animais de Doenças , Combinação de Medicamentos , Lipídeos/sangue , Masculino , Oxigênio/administração & dosagem , Ozônio/administração & dosagem , Fosfolipídeos/toxicidade , Coelhos , Sorbitol/toxicidade , Espectrofotometria
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