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1.
Nat Commun ; 11(1): 4482, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32901011

RESUMO

Intracellular trafficking governs receptor signaling, pathogenesis, immune responses and fate of nanomedicines. These processes are typically tracked by observing colocalization of fluorescent markers using confocal microscopy. However, this method is low throughput, limited by the resolution of microscopy, and can miss fleeting interactions. To address this, we developed a localization sensor composed of a quenched SNAP-tag substrate (SNAPSwitch) that can be conjugated to biomolecules using click chemistry. SNAPSwitch enables quantitative detection of trafficking to locations of interest within live cells using flow cytometry. Using SNAPSwitch, we followed the trafficking of DNA complexes from endosomes into the cytosol and nucleus. We show that antibodies against the transferrin or hyaluronan receptor are initially sorted into different compartments following endocytosis. In addition, we can resolve which side of the cellular membrane material was located. These results demonstrate SNAPSwitch is a high-throughput and broadly applicable tool to quantitatively track localization of materials in cells.


Assuntos
DNA/metabolismo , Sondas Moleculares/química , Nanopartículas/metabolismo , Proteínas/metabolismo , Animais , Transporte Biológico Ativo , Técnicas Biossensoriais/métodos , Química Click , Citometria de Fluxo , Corantes Fluorescentes , Células HEK293 , Humanos , Camundongos , Microscopia Confocal , Técnicas de Sonda Molecular , Sondas Moleculares/metabolismo , Células NIH 3T3
2.
Int J Nanomedicine ; 15: 5073-5082, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764937

RESUMO

Objective: To prepare xanthatin (XA)-loaded polydopamine (PDA) nanoparticles (PDA-XA-NPs) and to investigate their adhesion and bioavailability. Materials and methods: PDA-XA-NPs were synthesized and characterized using transmission electron microscopy, zeta potential analysis and encapsulation efficiency analysis. Their in vitro release kinetics and inhibitory effects on gastric cancer were studied. The adhesion of PDA-XA-NPs was evaluated by in vivo imaging atlas. The pharmacokinetics of PDA-XA-NPs and XA was compared. Results: PDA-XA-NPs had a spherical shape, a particle size of about 380 nm, an encapsulation efficiency of (82.1 ± 0.02) % and a drug loading capacity of (5.5 ± 0.1)%. The release of PDA-XA-NPs in PBS was stable and slow, without being affected by pH. The adhesion capacity of PDA-XA-NPs for mucin was significantly higher than that of bulk drug. The gastric mucosal retention of PDA-XA-NPs reached 89.1% which significantly exceeded that of XA. In vivo imaging showed that PDA-XA-NPs targeting the stomach were retained for a period of time. The pharmacokinetics study showed that PDA-XA-NPs had a longer retention time and a slower drug release than those of XA. In vitro experiments confirmed that PDA-XA-NPs exerted similar inhibitory effects on gastric cancer to those of XA, which lasted for a period of time. Conclusion: High-adhesion NPs were constructed. Gastric cancer was targeted by orally administered PDA-XA-NPs, as a potentially feasible therapy. Eventually, the bioavailability of XA was increased.


Assuntos
Antineoplásicos Fitogênicos/farmacocinética , Furanos/farmacocinética , Nanopartículas/química , Neoplasias Gástricas/tratamento farmacológico , Animais , Antineoplásicos Fitogênicos/química , Disponibilidade Biológica , Linhagem Celular Tumoral , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Furanos/química , Mucosa Gástrica/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Indóis/química , Masculino , Camundongos Endogâmicos ICR , Microscopia Eletrônica de Transmissão , Nanopartículas/metabolismo , Tamanho da Partícula , Polímeros/química , Ratos Sprague-Dawley , Neoplasias Gástricas/patologia
3.
Ecotoxicol Environ Saf ; 203: 111032, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32745774

RESUMO

Titanium dioxide nanoparticles (Np-TiO2) have become the common component of sunscreen cosmetic products. Np-TiO2 can affect especially aquatic ecosystems health, including aquatic organisms such as fish. It is therefore necessary to acquire a better understanding of the effect of Np-TiO2 on aquatic organisms. This study evaluated the biological effects of Np-TiO2 on Danio rerio, such as survival rate and weight change and, in particular, the Ti content or retention in the intestine and liver, as well as the activities of catalase and superoxide dismutase enzymes. In addition, the structure of the intestine, kidney, and liver was investigated through histological analysis. Ninety zebrafish were used, randomly divided into three treatment-groups: a control group (fed with food without adding Np-TiO2) and two groups of fish fed with food containing Np-TiO2 exposed for 7 and 14 days. The amount of Ti in the liver and intestine was measured using atomic absorption spectrophotometry coupled to a graphite furnace (GFAAS). Morphological analysis and enzyme catalase and superoxide dismutase assays were likewise performed. Ti was detected in all fish even in control group; probably Ti must have been introduced during production by the fish food industry. Structural changes were detected in fish fed with Np-TiO2 as vacuolization and disruption of the apical cytoplasm of epithelial cells that covered the intestinal villi. Although kidney morphology appeared intact, the lumen of the proximal tubule was enlarged, and the cells of the distal tubule were vacuolated. No morphological changes in the liver were detected; however, superoxide dismutase activity decreased, suggesting that liver changes occurred at the molecular level. Thus, Np-TiO2 causes morphological changes in the intestine, kidney, and liver of zebrafish and biochemical changes in the liver exposed for 7 and 14 days. Although not highly lethal, Np-TiO2 in the food chain can interfere with the morphophysiology of aquatic organisms. Neither mortalities nor body weight losses were recorded among fish in all groups over the duration of the experiment.


Assuntos
Mucosa Intestinal/efeitos dos fármacos , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Nanopartículas/toxicidade , Titânio/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra , Animais , Bioacumulação , Catalase , Relação Dose-Resposta a Droga , Ecossistema , Cadeia Alimentar , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Rim/metabolismo , Rim/patologia , Fígado/metabolismo , Fígado/patologia , Nanopartículas/metabolismo , Distribuição Aleatória , Protetores Solares/química , Titânio/metabolismo , Poluentes Químicos da Água/metabolismo
4.
Ecotoxicol Environ Saf ; 203: 110951, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32678752

RESUMO

The growing use of rare-earth doped upconversion nanoparticles (UCNPs) has caused increasing concern about their biosafety. Here, to understand the toxicity of UCNPs and their mechanism in HepG2 cells, we systematically study the cytotoxicity, uptake and elimination behaviors of three types of UCNPs combined multiple cytotoxicity evaluation means with inductively coupled plasma mass spectrometry (ICP-MS) detection. Sodium yttrium fluoride, doped with 18% (molar ratio) ytterbium and 2% erbium (NaYF4: Yb3+, Er3+) was selected as the model UCNPs with two sizes (35 and 55 nm), and the poly(acrylic acid) and polyethylenimine were selected as the representatives of negative and positive surface coating of UCNPs, respectively. UCNPs were found to induce cytotoxicity in time- and dose-dependent manners, which might be mediated by reactive oxygen species generation and oxidative stress. Apoptosis, inflammation, and metabolic process were enhanced after cells exposed to 200 mg/L UCNPs for 48 h. Increase in the protein levels of cleaved caspased-9, cleaved caspase-3 and Bax and decrease in the anti-apoptotic protein, Bcl-2 suggested that the mitochondria mediated pathway was involved in UCNP-induced apoptosis. With the aid of ICP-MS, it demonstrated that the cytotoxicity was associated with internalized amount of UCNPs, which largely relied on their surface properties rather than size in the tested range. By comparing UCNPs with Y3+ ions, it demonstrated that NPs properties played a nonnegligible role in the cytotoxicity of UCNPs. These findings provide new insights for fundamental understanding of cytotoxicity of UCNPs and may contribute to more rational use of these materials in the future.


Assuntos
Endocitose/efeitos dos fármacos , Érbio/toxicidade , Fluoretos/toxicidade , Nanopartículas/toxicidade , Itérbio/toxicidade , Ítrio/toxicidade , Apoptose/efeitos dos fármacos , Técnicas de Cultura de Células , Sobrevivência Celular , Érbio/química , Érbio/metabolismo , Fluoretos/química , Fluoretos/metabolismo , Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Nanopartículas/química , Nanopartículas/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Tamanho da Partícula , Propriedades de Superfície , Itérbio/química , Itérbio/metabolismo , Ítrio/química , Ítrio/metabolismo
5.
Proc Natl Acad Sci U S A ; 117(31): 18719-18728, 2020 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-32690692

RESUMO

CD4-based decoy approaches against HIV-1 are attractive options for long-term viral control, but initial designs, including soluble CD4 (sCD4) and CD4-Ig, were ineffective. To evaluate a therapeutic that more accurately mimics HIV-1 target cells compared with monomeric sCD4 and dimeric CD4-Ig, we generated virus-like nanoparticles that present clusters of membrane-associated CD4 (CD4-VLPs) to permit high-avidity binding of trimeric HIV-1 envelope spikes. In neutralization assays, CD4-VLPs were >12,000-fold more potent than sCD4 and CD4-Ig and >100-fold more potent than the broadly neutralizing antibody (bNAb) 3BNC117, with >12,000-fold improvements against strains poorly neutralized by 3BNC117. CD4-VLPs also neutralized patient-derived viral isolates that were resistant to 3BNC117 and other bNAbs. Intraperitoneal injections of CD4-CCR5-VLP produced only subneutralizing plasma concentrations in HIV-1-infected humanized mice but elicited CD4-binding site mutations that reduced viral fitness. All mutant viruses showed reduced sensitivity to sCD4 and CD4-Ig but remained sensitive to neutralization by CD4-VLPs in vitro. In vitro evolution studies demonstrated that CD4-VLPs effectively controlled HIV-1 replication at neutralizing concentrations, and viral escape was not observed. Moreover, CD4-VLPs potently neutralized viral swarms that were completely resistant to CD4-Ig, suggesting that escape pathways that confer resistance against conventional CD4-based inhibitors are ineffective against CD4-VLPs. These findings suggest that therapeutics that mimic HIV-1 target cells could prevent viral escape by exposing a universal vulnerability of HIV-1: the requirement to bind CD4 on a target cell. We propose that therapeutic and delivery strategies that ensure durable bioavailability need to be developed to translate this concept into a clinically feasible functional cure therapy.


Assuntos
Antígenos CD4 , HIV-1 , Nanopartículas , Vírion , Fármacos Anti-HIV , Antígenos CD4/química , Antígenos CD4/metabolismo , Linhagem Celular , HIV-1/química , HIV-1/genética , HIV-1/metabolismo , Humanos , Mimetismo Molecular , Nanomedicina/métodos , Nanopartículas/química , Nanopartículas/metabolismo , Vírion/química , Vírion/metabolismo
6.
Nanotoxicology ; 14(7): 985-1007, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32619159

RESUMO

Recent studies reported adverse liver effects and intestinal tumor formation after oral exposure to titanium dioxide (TiO2). Other oral toxicological studies, however, observed no effects on liver and intestine, despite prolonged exposure and/or high doses. In the present assessment, we aimed to better understand whether TiO2 can induce such effects at conditions relevant for humans. Therefore, we focused not only on the clinical and histopathological observations, but also used Adverse Outcome Pathways (AOPs) to consider earlier steps (Key Events). In addition, aiming for a more accurate risk assessment, the available information on organ concentrations of Ti (resulting from exposure to TiO2) from oral animal studies was compared to recently reported concentrations found in human postmortem organs. The overview obtained with the AOP approach indicates that TiO2 can trigger a number of key events in liver and intestine: Reactive Oxygen Species (ROS) generation, induction of oxidative stress and inflammation. TiO2 seems to be able to exert these early effects in animal studies at Ti liver concentrations that are only a factor of 30 and 6 times higher than the median and highest liver concentration found in humans, respectively. This confirms earlier conclusions that adverse effects on the liver in humans as a result of (oral) TiO2 exposure cannot be excluded. Data for comparison with Ti levels in human intestinal tissue, spleen and kidney with effect concentrations were too limited to draw firm conclusions. The Ti levels, though, are similar or higher than those found in liver, suggesting these tissues may be relevant too.


Assuntos
Mucosa Intestinal/efeitos dos fármacos , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Nanopartículas/toxicidade , Baço/efeitos dos fármacos , Titânio/toxicidade , Administração Oral , Animais , Aditivos Alimentares/química , Aditivos Alimentares/metabolismo , Aditivos Alimentares/toxicidade , Humanos , Inflamação , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Rim/metabolismo , Rim/patologia , Fígado/metabolismo , Fígado/patologia , Nanopartículas/química , Nanopartículas/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Baço/metabolismo , Baço/patologia , Titânio/química , Titânio/metabolismo
7.
Proc Natl Acad Sci U S A ; 117(32): 19141-19150, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32703811

RESUMO

Current strategies to direct therapy-loaded nanoparticles to the brain rely on functionalizing nanoparticles with ligands which bind target proteins associated with the blood-brain barrier (BBB). However, such strategies have significant brain-specificity limitations, as target proteins are not exclusively expressed at the brain microvasculature. Therefore, novel strategies which exploit alternative characteristics of the BBB are required to overcome nonspecific nanoparticle targeting to the periphery, thereby increasing drug efficacy and reducing detrimental peripheral side effects. Here, we present a simple, yet counterintuitive, brain-targeting strategy which exploits the higher impermeability of the BBB to selectively label the brain endothelium. This is achieved by harnessing the lower endocytic rate of brain endothelial cells (a key feature of the high BBB impermeability) to promote selective retention of free, unconjugated protein-binding ligands on the surface of brain endothelial cells compared to peripheral endothelial cells. Nanoparticles capable of efficiently binding to the displayed ligands (i.e., labeled endothelium) are consequently targeted specifically to the brain microvasculature with minimal "off-target" accumulation in peripheral organs. This approach therefore revolutionizes brain-targeting strategies by implementing a two-step targeting method which exploits the physiology of the BBB to generate the required brain specificity for nanoparticle delivery, paving the way to overcome targeting limitations and achieve clinical translation of neurological therapies. In addition, this work demonstrates that protein targets for brain delivery may be identified based not on differential tissue expression, but on differential endocytic rates between the brain and periphery.


Assuntos
Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Portadores de Fármacos/metabolismo , Sistemas de Liberação de Medicamentos/instrumentação , Células Endoteliais/metabolismo , Nanopartículas/metabolismo , Animais , Transporte Biológico , Encéfalo/irrigação sanguínea , Endotélio/metabolismo , Humanos , Ratos , Ratos Sprague-Dawley
8.
Nanotoxicology ; 14(6): 847-865, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32536243

RESUMO

To determine responses to nanoparticles in a more comprehensive way, current efforts in nanosafety aim at combining the analysis of multiple endpoints and comparing outcomes in different models. To this end, here we used tissue slices from mice as 3D ex vivo models and performed for the first time a comparative study of uptake and impact in liver, lung, and kidney slices exposed under the same conditions to silica, carboxylated and amino-modified polystyrene. In all organs, only exposure to amino-modified polystyrene induced toxicity, with stronger effects in kidneys and lungs. Uptake and distribution studies by confocal microscopy confirmed nanoparticle uptake in all slices, and, in line with what observed in vivo, preferential accumulation in the macrophages. However, uptake levels in kidneys were minimal, despite the strong impact observed when exposed to the amino-modified polystyrene. On the contrary, nanoparticle uptake and accumulation in macrophages were particularly evident in lung slices. Thus, tissue digestion was used to recover all cells from lung slices at different exposure times and to determine by flow cytometry detailed uptake kinetics in lung macrophages and all other cells, confirming higher uptake by the macrophages. Finally, the expression levels of a panel of targets involved in inflammation and macrophage polarization were measured to determine potential effects induced in lung and liver tissue. Overall, this comparative study allowed us to determine uptake and impact of nanoparticles in real tissue and identify important differences in outcomes in the organs in which nanoparticles distribute.


Assuntos
Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Nanopartículas/toxicidade , Poliestirenos/toxicidade , Animais , Feminino , Técnicas In Vitro , Inflamação , Rim/metabolismo , Fígado/metabolismo , Pulmão/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos Alveolares/efeitos dos fármacos , Macrófagos Alveolares/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Nanopartículas/metabolismo , Especificidade de Órgãos , Poliestirenos/metabolismo , Técnicas de Cultura de Tecidos , Distribuição Tecidual
9.
Nanotoxicology ; 14(6): 827-846, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32552239

RESUMO

Prior studies showed nanoparticle clearance was different in C57BL/6 versus BALB/c mice, strains prone to Th1 and Th2 immune responses, respectively. Objective: Assess nanoceria (cerium oxide, CeO2 nanoparticle) uptake time course and organ distribution, cellular and oxidative stress, and bioprocessing as a function of mouse strain. Methods: C57BL/6 and BALB/c female mice were i.p. injected with 10 mg/kg nanoceria or vehicle and terminated 0.5 to 24 h later. Organs were collected for cerium analysis; light and electron microscopy with elemental mapping; and protein carbonyl, IL-1ß, and caspase-1 determination. Results: Peripheral organ cerium significantly increased, generally more in C57BL/6 mice. Caspase-1 was significantly elevated in the liver at 6 h, to a greater extent in BALB/c mice, suggesting inflammasome pathway activation. Light microscopy revealed greater liver vacuolation in C57BL/6 mice and a nanoceria-induced decrease in BALB/c but not C57BL/6 mice vacuolation. Nanoceria increased spleen lymphoid white pulp cell density in BALB/c but not C57BL/6 mice. Electron microscopy showed intracellular nanoceria particles bioprocessed to form crystalline cerium phosphate nanoneedles. Ferritin accumulation was greatly increased proximal to the nanoceria, forming core-shell-like structures in C57BL/6 but even distribution in BALB/c mice. Conclusions: BALB/c mice were more responsive to nanoceria-induced effects, e.g. liver caspase-1 activation, reduced liver vacuolation, and increased spleen cell density. Nanoceria uptake, initiation of bioprocessing, and crystalline cerium phosphate nanoneedle formation were rapid. Ferritin greatly increased with a macrophage phenotype-dependent distribution. Further study will be needed to understand the mechanisms underlying the observed differences.


Assuntos
Cério/toxicidade , Fígado/efeitos dos fármacos , Nanopartículas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Baço/efeitos dos fármacos , Animais , Cério/química , Cério/metabolismo , Feminino , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Microscopia Eletrônica , Nanopartículas/química , Nanopartículas/metabolismo , Fosfatos/metabolismo , Especificidade da Espécie , Baço/metabolismo , Propriedades de Superfície , Distribuição Tecidual
10.
Ecotoxicol Environ Saf ; 200: 110776, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32474243

RESUMO

Over the past decades, titanium dioxide nanoparticles (n-TiO2) have been extensively used in several industrial applications and the manufacture of novel consumer products. Although strict regulations have been put in place to limit their release into the aquatic environment, these nanoparticles can still be found at elevated levels within the environment, which can result in toxic effects on exposed organisms and has possible implications in term of public health. Bivalve mollusks are a unique and ideal group of shellfish for the study and monitoring the aquatic pollution by n-TiO2 because of their filter-feeding behaviour and ability to accumulate toxicants in their tissues. In these animals, exposure to n-TiO2 leads to oxidative stress, immunotoxicity, neurotoxicity, and genotoxicity, as well as behavioral and physiological changes. This review summarizes the uptake, accumulation, and fate of n-TiO2 in aquatic environments and the possible interactions between n-TiO2 and other contaminants such as heavy metals and organic pollutants. Moreover, the toxicological impacts and mechanisms of action are discussed for a wide range of bivalve mollusks. This data underlines the pressing need for additional knowledge and future research plans for the development of control strategies to mitigate the release of n-TiO2 to the aquatic environment to prevent the toxicological impacts on bivalves and protect public health.


Assuntos
Bivalves/efeitos dos fármacos , Nanopartículas/toxicidade , Titânio/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Bioacumulação , Bivalves/genética , Bivalves/metabolismo , Dano ao DNA , Ecotoxicologia , Metais Pesados/metabolismo , Metais Pesados/toxicidade , Nanopartículas/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , Frutos do Mar , Titânio/metabolismo , Poluentes Químicos da Água/metabolismo
11.
Food Chem ; 329: 127224, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32516716

RESUMO

To overcome the drawbacks of antibody labeling dependence and single-readout system in the conventional lateral flow immunoassays (LFIAs) as well as the non-targeted combination of new capture agents reported recently for pathogen detection, in this work, a multi-readout and label-free LFIA was proposed for rapid detection of Escherichia coli O157:H7 (E. coli O157:H7) based on a nanozyme-bacteria-antibody sandwich pattern. A type of functional nanozyme-mannose modified Prussian blue (man-PB), was introduced as the recognition agent as well as signal indicator. Apart from original signal intensity on the T-line, the peroxidase-like catalytic activity-driven generation of colorimetric signal could be used as another format of quantitation. Importantly, such LFIA could exhibit excellent performance for target pathogens detection separately with a quantitative range of 102-108 cfu·mL-1 and a low detection limit of 102 cfu·mL-1 based on different readout formats, indicating the application potential of the proposed LFIA in real samples.


Assuntos
Escherichia coli O157/isolamento & purificação , Imunoensaio , Nanopartículas/química , Anticorpos Antibacterianos/química , Anticorpos Antibacterianos/imunologia , Catálise , Colorimetria , Escherichia coli O157/imunologia , Ferrocianetos/química , Microbiologia de Alimentos , Limite de Detecção , Manose/química , Nanopartículas/metabolismo
12.
AAPS PharmSciTech ; 21(5): 170, 2020 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-32529303

RESUMO

Felodipine (FLD), a dihydropyridine calcium channel blocker with excellent antihypertensive effect, is poorly soluble and undergoes extensive hepatic metabolism, which lead to poor oral bioavailability (about 15%) and limit its clinic application. The goal of this study was to develop solid lipid nanoparticles (SLNs) loading FLD to improve the oral bioavailability. The FLD loaded solid lipid nanoparticles (FLD-SLNs) were prepared by the effervescent dispersion technique developed by our laboratory, which might have some advantages over traditional methods. The FLD-SLNs showed desired particle characteristics with particle size (198.15 ± 1.82 nm), poly dispersity index (0.26 ± 0.02), zeta-potential (- 25.53 ± 0.60 mV), entrapment efficiency (95.65 ± 0.70%), drug loading (2.33 ± 0.10%), and a spherical appearance. Pharmacokinetic results showed that the FLD-SLNs presented 3.17-fold increase in area under the curve (AUC(0-t)) compared with free FLD after oral administration in beagle dogs, which indicated that SLNs prepared using the effervescent dispersion technique can improve the bioavailability of lipophilic drugs like felodipine by enhancement of absorption and reduction first-pass metabolism.


Assuntos
Bloqueadores dos Canais de Cálcio/farmacocinética , Química Farmacêutica/métodos , Felodipino/farmacocinética , Nanopartículas/metabolismo , Administração Oral , Animais , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/síntese química , Anti-Hipertensivos/farmacocinética , Disponibilidade Biológica , Bloqueadores dos Canais de Cálcio/administração & dosagem , Bloqueadores dos Canais de Cálcio/síntese química , Estudos Cross-Over , Cães , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/síntese química , Portadores de Fármacos/farmacocinética , Felodipino/administração & dosagem , Felodipino/síntese química , Lipídeos , Masculino , Nanopartículas/administração & dosagem , Nanopartículas/química , Tamanho da Partícula , Distribuição Aleatória
13.
Ecotoxicol Environ Saf ; 202: 110884, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32563952

RESUMO

Nanotoxicity to fetal brains after maternal oral exposures during pregnancy is often in question because nanoparticles have to cross multiple biological barriers such as intestinal barrier, maternal blood placental barrier (BPB) and fetal blood brain barrier (BBB). Here, we investigated this seemingly impossible passage for ZrO2 nanoparticles (ZrO2 NPs) from maternal body to fetal brains using a pregnant mouse model. After three oral exposures to pregnant mice at late pregnancy (GD16, 17, 18), ZrO2 NPs were able to accumulate in fetal brains at GD19 via crossing the well-developed maternal BPB and fetal BBB. Moreover, ZrO2 NPs crossed the mature biological barriers with increasing the expression levels of caveolae, clathrin and arf6 proteins as well as decreasing the expression levels of the tight junction proteins claudin-5, occludin and ZO-1 in placenta and fetal brain. From this investigation, we speculated that the main mechanisms for such translocation were receptor-mediated endocytosis transcellular pathway and breakthrough of tight junctions paracellular pathway in mature maternal BPB and fetal BBB. These findings have important implications for other nanoparticles exposures during pregnancy and provide crucial information to safeguard fetal development from contamination of widely used nanoproducts.


Assuntos
Barreira Hematoencefálica/metabolismo , Nanopartículas/metabolismo , Óxido de Zinco/metabolismo , Animais , Transporte Biológico , Endocitose , Feminino , Desenvolvimento Fetal , Feto , Humanos , Exposição Materna , Camundongos , Ocludina/metabolismo , Placenta/metabolismo , Gravidez , Junções Íntimas/metabolismo
14.
AAPS PharmSciTech ; 21(4): 132, 2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32409932

RESUMO

The superiority of nanomedicine over conventional medicines in the treatment of cancer has gained immediate recognition worldwide. As traditional cancer therapies are nonspecific and detrimental to healthy cells, the ability of nanomedicine to release drugs to target tumor cells specifically instead of healthy cells has brought new hope to cancer patients. This review focuses on the effects of various factors of nanoparticles such as transport, concentration in cells, tumor microenvironment, interaction with protein, penetration, uptake by tumor cells, cancer cell mutations, and intracellular trafficking of the nanoparticle. Besides the history of nanomedicine, future perspectives of nanomedicines are also explored in this text.


Assuntos
Antineoplásicos/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Nanomedicina/métodos , Nanopartículas/administração & dosagem , Neoplasias/tratamento farmacológico , Microambiente Tumoral/efeitos dos fármacos , Animais , Antineoplásicos/química , Antineoplásicos/metabolismo , Humanos , Nanopartículas/química , Nanopartículas/metabolismo , Neoplasias/metabolismo , Microambiente Tumoral/fisiologia
15.
AAPS PharmSciTech ; 21(4): 134, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32415347

RESUMO

This work described the development of a cationic polylactic acid (PLA)-based nanoparticles (NPs) as an antigen delivery system using dimethyldioctadecylammonium bromide (DDA) to facilitate the engulfment of BSA-FITC by porcine alveolar macrophages (3D4/2 cells) and heat-labile enterotoxin subunit B (LTB) to enhance the transport of BSA-FITC across M cells. The experimental design methodology was employed to study the influence of PLA, polyvinyl alcohol (PVA), DDA, and LTB on the physical properties of the PLA-based NPs. The size of selected cationic PLA NPs comprising 5% PLA, 5% PVA, and 0.6% DDA with or without LTB absorption was range from 367 to 390 nm with a polydispersity index of 0.26, a zeta potential of + 26.00 to + 30.55 mV, and entrapment efficiency of 41.43%. Electron micrographs revealed NPs with spherical shape. The release kinetic of BSA from the NPs followed the Korsmeyer-Peppas kinetics. The cationic PLA NPs with LTB surface absorption showed 3-fold increase in BSA-FITC transported across M cells compared with the NPs without LTB absorption. The uptake studies demonstrated 2-fold increase in BSA-FITC intensity in 3D4/2 cells with cationic NPs as compared with anionic NPs. Overall, the results suggested that LTB decreased the retention time of BSA-FITC loaded in the cationic PLA NPs within the M cells, thus promoting the transport of BSA-FITC across the M cells, and cationic NPs composed of DDA help facilitate the uptake of BSA-FITC in the 3D4/2 cells. Further studies in pigs with respiratory antigens will provide information on the efficacy of cationic PLA NPs as a nasal antigen carrier system.


Assuntos
Fluoresceína-5-Isotiocianato/análogos & derivados , Macrófagos Alveolares/metabolismo , Nanopartículas/metabolismo , Poliésteres/metabolismo , Soroalbumina Bovina/metabolismo , Animais , Cátions , Linhagem Celular , Técnicas de Cocultura , Fluoresceína-5-Isotiocianato/administração & dosagem , Fluoresceína-5-Isotiocianato/química , Fluoresceína-5-Isotiocianato/metabolismo , Macrófagos Alveolares/efeitos dos fármacos , Nanopartículas/administração & dosagem , Nanopartículas/química , Tamanho da Partícula , Poliésteres/administração & dosagem , Poliésteres/química , Soroalbumina Bovina/administração & dosagem , Soroalbumina Bovina/química , Suínos
16.
Nat Commun ; 11(1): 2622, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32457361

RESUMO

Vascular disease remains the leading cause of death and disability, the etiology of which often involves atherosclerosis. The current treatment of atherosclerosis by pharmacotherapy has limited therapeutic efficacy. Here we report a biomimetic drug delivery system derived from macrophage membrane coated ROS-responsive nanoparticles (NPs). The macrophage membrane not only avoids the clearance of NPs from the reticuloendothelial system, but also leads NPs to the inflammatory tissues, where the ROS-responsiveness of NPs enables specific payload release. Moreover, the macrophage membrane sequesters proinflammatory cytokines to suppress local inflammation. The synergistic effects of pharmacotherapy and inflammatory cytokines sequestration from such a biomimetic drug delivery system lead to improved therapeutic efficacy in atherosclerosis. Comparison to macrophage internalized with ROS-responsive NPs, as a live-cell based drug delivery system for treatment of atherosclerosis, suggests that cell membrane coated drug delivery approach is likely more suitable for dealing with an inflammatory disease than the live-cell approach.


Assuntos
Aterosclerose/tratamento farmacológico , Citocinas/metabolismo , Sistemas de Liberação de Medicamentos , Macrófagos/metabolismo , Nanopartículas/metabolismo , Animais , Aorta/efeitos dos fármacos , Aorta/metabolismo , Aterosclerose/metabolismo , Atorvastatina/uso terapêutico , Materiais Biomiméticos , Membrana Celular/metabolismo , Liberação Controlada de Fármacos , Feminino , Camundongos , Células RAW 264.7 , Espécies Reativas de Oxigênio/metabolismo , Resultado do Tratamento
17.
Phys Med Biol ; 65(12): 125017, 2020 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-32460260

RESUMO

Nanocarriers offer a promising approach to significantly improve therapeutic delivery to solid tumors as well as limit the side effects associated with anti-cancer agents. However, their relatively large size can negatively affect their ability to efficiently penetrate into more interior tumor regions, ultimately reducing therapeutic efficacy. Poor penetration of large agents such as nanocarriers is attributed to factors in the tumor microenvironment such as elevated interstitial fluid pressure (IFP) and fibrillar collagen in the extracellular matrix. Our previous studies reported that pretreatment of solid tumor xenografts with nondestructive pulsed focused ultrasound (pFUS) can improve the delivery and subsequent therapy of a variety of therapeutic formulations in different tumor models, where the results were associated with expanded extracellular spaces (ECS), an increase in hydraulic conductivity, and decrease in tissue stiffness. Here, we demonstrate the inverse relationship between IFP and the penetration of systemically administered nanoparticle (NP) probes, where IFP increased from the tumor periphery to their center. Furthermore, we show that pretreatment with pFUS can safely reduce IFP and improve NP delivery; especially into the center of the tumors. These results coincide with effects generated in the fibrillar collagen network microstructure in the ECS as determined by quantitative polarized light microscopy. Whole tumor and histomorphometric analysis, however, did not show significant differences in collagen area fraction or collagen feature solidity, as well as tumor cross-sectional area and aspect ratio, as a result of the treatments. We present a biophysical model connecting the experimental results, where pFUS-mediated cytoarchitectural changes are associated with improved redistribution of the interstitial fluid and lower IFP. The resulting improvement in NP delivery supports our previous therapeutic studies and may have implications for clinical applications to improve therapeutic outcomes in cancer therapy.


Assuntos
Transformação Celular Neoplásica , Líquido Extracelular/metabolismo , Nanopartículas/metabolismo , Pressão , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Ondas Ultrassônicas , Animais , Transporte Biológico , Humanos
18.
Proc Natl Acad Sci U S A ; 117(19): 10492-10499, 2020 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-32332167

RESUMO

Protein corona formation is critical for the design of ideal and safe nanoparticles (NPs) for nanomedicine, biosensing, organ targeting, and other applications, but methods to quantitatively predict the formation of the protein corona, especially for functional compositions, remain unavailable. The traditional linear regression model performs poorly for the protein corona, as measured by R 2 (less than 0.40). Here, the performance with R 2 over 0.75 in the prediction of the protein corona was achieved by integrating a machine learning model and meta-analysis. NPs without modification and surface modification were identified as the two most important factors determining protein corona formation. According to experimental verification, the functional protein compositions (e.g., immune proteins, complement proteins, and apolipoproteins) in complex coronas were precisely predicted with good R 2 (most over 0.80). Moreover, the method successfully predicted the cellular recognition (e.g., cellular uptake by macrophages and cytokine release) mediated by functional corona proteins. This workflow provides a method to accurately and quantitatively predict the functional composition of the protein corona that determines cellular recognition and nanotoxicity to guide the synthesis and applications of a wide range of NPs by overcoming limitations and uncertainty.


Assuntos
Previsões/métodos , Nanopartículas/metabolismo , Coroa de Proteína/metabolismo , Animais , Humanos , Aprendizado de Máquina , Macrófagos , Camundongos , Modelos Teóricos , Proteínas , Células RAW 264.7
19.
AAPS PharmSciTech ; 21(4): 118, 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32318890

RESUMO

Pentoxifylline (PTX), an anti-hemorrhage drug used in the treatment of intermittent claudication, is extensively metabolized by the liver resulting in a reduction of the therapeutic levels within a short duration of time. Self-nano-emulsifying drug delivery system (SNEDDS) is well reported to enhance the bio-absorption of drugs by forming nano-sized globules upon contact with the biological fluids after oral administration. The present study aimed to formulate, characterize, and improve the oral bioavailability of PTX using SNEDDS. The formulated SNEDDS consisted of palm oil, Capmul® MCM, and Tween® 80 as oil, surfactant, and co-surfactant, respectively. The mixture design module under the umbrella of the design of experiments was used for the optimization of SNEDDS. The dynamic light-scattering technique was used to confirm the formation of nanoemulsion based on the globule size, in addition to the turbidity measurements. In vivo bioavailability studies were carried out on male Wistar rats. The pharmacokinetic parameters upon oral administration were calculated using the GastroPlus software. The optimized SNEDDS had a mean globule size of 165 nm with minimal turbidity in an aqueous medium. Bioavailability of PTX increased 1.5-folds (AUC = 1013.30 ng h/mL) as SNEDDS than the pure drug with an AUC of 673.10 ng h/mL. In conclusion, SNEDDS was seen to enhance the bioavailability of PTX and can be explored to effectively control the incidents of intermittent claudication.


Assuntos
Caprilatos/farmacocinética , Sistemas de Liberação de Medicamentos/métodos , Emulsificantes/farmacocinética , Glicerídeos/farmacocinética , Nanopartículas/metabolismo , Óleo de Palmeira/farmacocinética , Pentoxifilina/farmacocinética , Administração Oral , Animais , Disponibilidade Biológica , Caprilatos/administração & dosagem , Liberação Controlada de Fármacos , Emulsificantes/administração & dosagem , Glicerídeos/administração & dosagem , Masculino , Nanopartículas/administração & dosagem , Óleo de Palmeira/administração & dosagem , Tamanho da Partícula , Pentoxifilina/administração & dosagem , Inibidores da Agregação de Plaquetas/administração & dosagem , Inibidores da Agregação de Plaquetas/farmacocinética , Ratos , Ratos Wistar
20.
Nanotoxicology ; 14(5): 696-710, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32301357

RESUMO

Cerium oxide nanoparticles (CeO2 NPs) are widely used in various commercial applications because of their characteristic properties. People can be easily exposed to CeO2 NPs in real life, but the safety assessment of CeO2 NPs has not been fully investigated. Therefore, in this study, we conducted a combined repeated-dose and reproductive/developmental toxicity screening study (OECD testing guideline 422) to investigate the potential hazards on human health, including reproductive/developmental functions, after repeated daily CeO2 NPs oral gavage administration to both males and females. In addition, tissues from parental animals and their pups were collected to analyze the internal accumulation of cerium. CeO2 NPs were orally administered to Sprague-Dawley rats at doses of 0, 100, 300 and 1000 mg/kg during their pre-mating, mating, gestation and early lactation periods. In the general systemic and reproductive/developmental examinations, no marked toxicities were observed in any in-life and terminal observation parameters in this study. In the biodistribution analysis, cerium was not detected in either parental or pup tissues (blood, liver, lungs and kidneys). Repeated oral exposure of CeO2 NPs did not induce marked toxicities affecting general systemic and reproductive/developmental functions up to the dose level of 1000 mg/kg and the CeO2 NPs were not systemically absorbed in parental animals or their pups. This result could be used in risk assessment for humans, and additional toxicity studies with CeO2 NPs will be necessary considering various physicochemical properties and exposure probabilities of these nanoparticles.


Assuntos
Cério/toxicidade , Nanopartículas/toxicidade , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Reprodução/efeitos dos fármacos , Administração Oral , Animais , Cério/química , Cério/farmacocinética , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Exposição Materna/efeitos adversos , Nanopartículas/química , Nanopartículas/metabolismo , Tamanho da Partícula , Exposição Paterna/efeitos adversos , Gravidez , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Ratos , Ratos Sprague-Dawley , Propriedades de Superfície , Distribuição Tecidual
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