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1.
NMR Biomed ; 30(11)2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28857310

RESUMO

Lung cancer is a primary cause of cancer deaths worldwide. Timely detection of this pathology is necessary to delay or interrupt lung cancer progression, ultimately resulting in a possible better prognosis for the patient. In this context, magnetic resonance imaging (MRI) is especially promising. Ultra-short echo time (UTE) MRI sequences, in combination with gadolinium-based contrast agents, have indeed shown to be especially adapted to the detection of lung neoplastic lesions at submillimeter precision. Manganese-enhanced MRI (MEMRI) increasingly appears to be a possible effective alternative to gadolinium-enhanced MRI. In this work, we investigated whether low-dose MEMRI can effectively target non-small-cell lung cancer in rodents, whilst minimizing the potential toxic effect of manganese. Both systemic and orotracheal administration modalities allowed the identification of tumors of submillimeter size, as confirmed by bioluminescence imaging and histology. Equivalent tumor signal enhancements and contrast-to-noise ratios were observed with orotracheal administration using 20 times lower doses compared with the more conventional systemic route. This finding is of crucial importance as it supports the observation that higher performances of contrast agents can be obtained using an orotracheal administration route when targeting lung diseases. As a consequence, lower concentrations of contrast media can be employed, reducing the dose and potential safety issues. The non-detectable accumulation of ionic manganese in the brain and liver following orotracheal administration observed in vivo is extremely encouraging with regard to the safety of the orotracheal protocol with low-dose Mn2+ administration. To our knowledge, this is the first time that a study has clearly allowed the high-precision detection of lung tumor and its contours via the synergic employment of a strongly T1 -weighted MRI UTE sequence and ionic manganese, an inexpensive contrast agent. Overall, these results support the growing interest in drug and contrast agent delivery via the airways to target and diagnose several diseases of the lungs.


Assuntos
Aumento da Imagem , Neoplasias Pulmonares/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Manganês/farmacologia , Animais , Meios de Contraste , Feminino , Camundongos
2.
Can J Physiol Pharmacol ; 95(4): 443-446, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28177696

RESUMO

A recent study showed that a significant fall in mean arterial pressure (MAP) occurred following intravenous injection of two novel superparamagnetic iron oxide nanoparticles (SPIONs), MF66 and OD15. To assess if this was caused by excessive glomerular clearance, the effect of both particles on renal function was studied. Experiments were performed on sodium pentobarbital anaesthetised male Wistar rats (250-350 g). Twenty-minute urine clearances were taken followed by an i.v. bolus of MF66, OD15 (2 mg·kg-1), or dH2O (0.4 mL·kg-1). MF6 or OD15 injection resulted in a significant transient drop in MAP and renal blood flow by approximately 33% and 50% (P < 0.05). The absolute excretion of sodium was significantly increased (P < 0.05) by almost 80% and 70% following OD15 and MF66, respectively. Similarly, fractional excretion of sodium was increased by almost 80% and 60% following OD15 and MF66, respectively. The glomerular filtration rate was not significantly affected, but urine flow increased nonsignificantly by approximately 50% and 66% following i.v. injection of OD15 and MF66, respectively. SPIONs produce a decrease in blood pressure and a natriuresis; however, the rate of fluid filtration in the kidney was not significantly affected.


Assuntos
Sistemas de Liberação de Medicamentos/efeitos adversos , Compostos Férricos/efeitos adversos , Taxa de Filtração Glomerular/efeitos dos fármacos , Hipotensão/induzido quimicamente , Nanopartículas de Magnetita/efeitos adversos , Natriurese/efeitos dos fármacos , Circulação Renal/efeitos dos fármacos , Anestesia Intravenosa , Animais , Diurese/efeitos dos fármacos , Compostos Férricos/administração & dosagem , Compostos Férricos/farmacocinética , Injeções Intravenosas , Imageamento por Ressonância Magnética/métodos , Nanopartículas de Magnetita/administração & dosagem , Nanopartículas de Magnetita/química , Masculino , Taxa de Depuração Metabólica , Modelos Animais , Pentobarbital/administração & dosagem , Ratos , Ratos Wistar
3.
Clin Exp Pharmacol Physiol ; 43(3): 319-26, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26707795

RESUMO

Manufactured nanomaterials have a variety of medical applications, including diagnosis and targeted treatment of cancer. A series of experiments were conducted to determine the pharmacokinetic, biodistribution and biocompatibility of two novel magnetic nanoparticles (MNPs) in the anaesthetized pig. Dimercaptosuccinic acid (DMSA) coated superparamagnetic iron oxide nanoparticles (MF66-labelled 12 nm, core nominal diameter and OD15 15 nm); at 0.5, or 2.0 mg/kg) were injected intravenously. Particles induced a dose-dependent decrease in blood pressure following administration which recovered to control levels several minutes after injection. Blood samples were collected for a 5-h period and stored for determination of particle concentration using particle electron paramagnetic resonance (pEPR). Organs were harvested post-mortem for magnetic resonance imaging (MRI at 1.5 T field strength) and histology. OD15 (2.0 mg/kg) MNP had a plasma half-life of approximately 15 min. Both doses of the MF66 (0.5 and 2.0 mg/kg) MNP were below detection limits. MNP accumulation was observed primarily in the liver and spleen with MRI scans which was confirmed by histology. MRI also showed that both MNPs were present in the lungs. The results show that further modifications may be required to improve the biocompatibility of these particles for use as diagnostic and therapeutic agents.


Assuntos
Compostos Férricos/química , Compostos Férricos/farmacocinética , Imãs , Suínos , Anestesia , Animais , Pressão Sanguínea/efeitos dos fármacos , Compostos Férricos/efeitos adversos , Compostos Férricos/sangue , Pulmão/citologia , Pulmão/efeitos dos fármacos , Imageamento por Ressonância Magnética , Tamanho da Partícula , Distribuição Tecidual
4.
Sci Rep ; 13(1): 5094, 2023 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-36991081

RESUMO

Malignant gliomas are a type of primary brain tumour that originates in glial cells. Among them, glioblastoma multiforme (GBM) is the most common and the most aggressive brain tumour in adults, classified as grade IV by the World Health Organization. The standard care for GBM, known as the Stupp protocol includes surgical resection followed by oral chemotherapy with temozolomide (TMZ). This treatment option provides a median survival prognosis of only 16-18 months to patients mainly due to tumour recurrence. Therefore, enhanced treatment options are urgently needed for this disease. Here we show the development, characterization, and in vitro and in vivo evaluation of a new composite material for local therapy of GBM post-surgery. We developed responsive nanoparticles that were loaded with paclitaxel (PTX), and that showed penetration in 3D spheroids and cell internalization. These nanoparticles were found to be cytotoxic in 2D (U-87 cells) and 3D (U-87 spheroids) models of GBM. The incorporation of these nanoparticles into a hydrogel facilitates their sustained release in time. Moreover, the formulation of this hydrogel containing PTX-loaded responsive nanoparticles and free TMZ was able to delay tumour recurrence in vivo after resection surgery. Therefore, our formulation represents a promising approach to develop combined local therapies against GBM using injectable hydrogels containing nanoparticles.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Nanocompostos , Nanopartículas , Adulto , Humanos , Glioblastoma/patologia , Preparações de Ação Retardada/uso terapêutico , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/patologia , Temozolomida/uso terapêutico , Paclitaxel , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Hidrogéis/uso terapêutico , Linhagem Celular Tumoral
5.
Nanotoxicology ; 17(8-9): 562-580, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37982374

RESUMO

Iron oxide nanoparticles (IONP) are showing promise in many biomedical applications. One of these- magnetic hyperthermia- utilizes externally applied alternating magnetic fields and tumor-residing magnetic nanoparticles to generate localized therapeutic temperature elevations. Magnetic hyperthermia is approved in Europe to treat glioblastoma and is undergoing clinical assessment in the United States to treat prostate cancer. In this study, we performed biodistribution and histological analysis of a new IONP (RCL-01) in Wistar rats. These nanoparticles are currently undergoing clinical assessment in locally advanced pancreatic ductal adenocarcinoma to determine the feasibility of magnetic hyperthermia treatment in this disease. The study presented here aimed to determine the fate of these nanoparticles in vivo and whether this results in organ damage. Wistar rats were injected intravenously with relatively high doses of IONP (30 mgFe/kg, 45 mgFe/kg and 60 mgFe/kg) and compared to a vehicle control to determine the accumulation of iron in organs and whether this resulted in histological changes in these tissues. Dose-dependent increases of iron were observed in the liver, spleen and lungs of IONP-treated animals at 7 days postinjection; however, this did not result in significant histological changes in these tissues. Immunofluorescent imaging determined these nanoparticles are internalized by macrophages in tissue, suggesting they are readily phagocytosed by the reticuloendothelial system for eventual recycling. Notably, no changes in iron or dextran staining were found in the kidneys across all treatment groups, providing evidence for potential renal clearance.


Assuntos
Nanopartículas de Magnetita , Nanopartículas , Ratos , Masculino , Animais , Ratos Wistar , Distribuição Tecidual , Dextranos , Nanopartículas de Magnetita/toxicidade , Compostos Férricos/toxicidade , Compostos Férricos/uso terapêutico , Ferro , Nanopartículas/toxicidade
6.
Magn Reson Med ; 68(1): 234-40, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22127903

RESUMO

Manganese-enhanced MRI (MEMRI) is a powerful technique for the in vivo monitoring of brain function in animals. Manganese enters into cells through calcium channels, i.e., voltage-gated calcium channels and activated glutamate receptors (e.g., N-methyl-D-aspartate receptors). N-methyl-D-aspartate receptors are activated both in normal physiological and pathophysiological conditions. Consistent with these mechanisms, we showed that in the olfactory bulb, the MEMRI signal strongly increases when excitotoxic mechanisms are induced by an administration of a N-methyl-D-aspartate receptor agonist, quinolinate. We found that the intensity of the MEMRI signal in excitotoxic conditions is similar to the odor-evoked signal in normal physiological conditions. Finally, we showed that the dynamics of the MEMRI signal are determined by the early phase of manganese in the olfactory bulb. Overall, these data show that, in addition to physiological studies, MEMRI can be used as an in vivo method to follow-up the dynamics of excitotoxic events.


Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Imageamento por Ressonância Magnética/métodos , Manganês/toxicidade , Olfato/fisiologia , Animais , Meios de Contraste/toxicidade , Aumento da Imagem/métodos , Masculino , Odorantes , Ácido Quinolínico/farmacologia , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Olfato/efeitos dos fármacos
7.
Pharm Res ; 29(6): 1425-34, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22322897

RESUMO

PURPOSE: To investigate DSPE-PEG(2000)-based micellar formulations of salmon calcitonin (sCT) for their ability to improve pulmonary delivery. METHODS: Micelles were characterised by DLS and (31)P-NMR spectroscopy. Stability against sCT degrading peptidases, trypsin, α-chymotrypsin and neutrophil elastase as well as their influence on transepithelial absorption was investigated in vitro. In vivo performance of sCT micelles was studied in an experimental model of intratracheal aerosolisation into rats. RESULTS: Micelles with a mean hydrodynamic diameter of 12 nm spontaneously assembled, when a total concentration of 0.02 mM of PEG-lipid and sCT (at 1:1 molar ratio) was exceeded. Nuclear magnetic resonance confirmed the presence of small micellar structures. The micellar formulation showed increased stability against enzymatic digestion. In vitro studies also showed that sCT micelles were able to enhance transepithelial absorption. Data obtained from in vivo experiments provided evidence of significantly (P < 0.05) higher mean plasma concentrations of sCT, after inhalation of micelles compared to sCT solution, at 60 and 90 min, a significantly higher AUC (inf) and a relative bioavailability of 160 ± 55% when compared to plain sCT solution. CONCLUSIONS: The herein described PEG-lipid micelles are promising carriers for enhanced pulmonary delivery of sCT.


Assuntos
Conservadores da Densidade Óssea/administração & dosagem , Calcitonina/administração & dosagem , Portadores de Fármacos , Micelas , Fosfatidiletanolaminas/química , Polietilenoglicóis/química , Absorção , Administração por Inalação , Aerossóis , Animais , Área Sob a Curva , Disponibilidade Biológica , Conservadores da Densidade Óssea/sangue , Conservadores da Densidade Óssea/química , Conservadores da Densidade Óssea/farmacocinética , Calcitonina/sangue , Calcitonina/química , Calcitonina/farmacocinética , Linhagem Celular , Química Farmacêutica , Quimotripsina/metabolismo , Composição de Medicamentos , Humanos , Elastase de Leucócito/metabolismo , Luz , Espectroscopia de Ressonância Magnética , Masculino , Tamanho da Partícula , Ratos , Ratos Wistar , Mucosa Respiratória/metabolismo , Espalhamento de Radiação , Tecnologia Farmacêutica/métodos , Tripsina/metabolismo
8.
Proc Natl Acad Sci U S A ; 106(42): 17817-22, 2009 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-19822744

RESUMO

Degenerative retinopathies, including age-related macular degeneration, diabetic retinopathy, and hereditary retinal disorders--major causes of world blindness--are potentially treatable by using low-molecular weight neuroprotective, antiapoptotic, or antineovascular drugs. These agents are, however, not in current systemic use owing to, among other factors, their inability to passively diffuse across the microvasculature of the retina because of the presence of the inner blood-retina barrier (iBRB). Moreover, preclinical assessment of the efficacies of new formulations in the treatment of such conditions is similarly compromised. We describe here an experimental process for RNAi-mediated, size-selective, transient, and reversible modulation of the iBRB in mice to molecules up to 800 Da by suppression of transcripts encoding claudin-5, a protein component of the tight junctions of the inner retinal vasculature. MRI produced no evidence indicative of brain or retinal edema, and the process resulted in minimal disturbance of global transcriptional patterns analyzed in neuronal tissue. We show that visual function can be improved in IMPDH1(-/-) mice, a model of autosomal recessive retinitis pigmentosa, and that the rate of photoreceptor cell death can be reduced in a model of light-induced retinal degeneration by systemic drug delivery after reversible barrier opening. These findings provide a platform for high-throughput drug screening in models of retinal degeneration, and they ultimately could result in the development of a novel "humanized" approach to therapy for conditions with little or no current forms of treatment.


Assuntos
Barreira Hematorretiniana/efeitos dos fármacos , Barreira Hematorretiniana/metabolismo , Sistemas de Liberação de Medicamentos , Oligopeptídeos/administração & dosagem , Animais , Calpaína/antagonistas & inibidores , Claudina-5 , Inibidores de Cisteína Proteinase/administração & dosagem , Modelos Animais de Doenças , Eletrorretinografia , Guanosina Trifosfato/administração & dosagem , Guanosina Trifosfato/metabolismo , Humanos , IMP Desidrogenase/deficiência , IMP Desidrogenase/genética , Imageamento por Ressonância Magnética , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Interferência de RNA , RNA Interferente Pequeno/genética , Retina/efeitos dos fármacos , Retina/metabolismo , Retinose Pigmentar/tratamento farmacológico , Retinose Pigmentar/genética , Retinose Pigmentar/metabolismo
9.
Colloids Surf B Biointerfaces ; 214: 112463, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35316703

RESUMO

A drug delivery nanosystem of noble bimetallic nanoparticles (NPs) which consists of Au NPs capped with Pt NPs (Au@Pt NPs) is constructed and functionalised with a quinazoline based small molecule (Au@Pt@Q NPs), acting as a theranostic agent against glioblastoma. Two different hydrothermal synthetic procedures for bimetallic Au@Pt NPs are presented and the resulting nanostructures are fully characterised by means of spectroscopic and microscopic methods. The imaging and targeting capacity of the new drug delivery system is assessed through fluorescent optical microscopy and cytotoxicity evaluations. The constructed Au@Pt NPs consist a monodispersed colloidal solution of 25 nm with photoluminescent, fluorescent and X-Ray absorption properties that confirm their diagnostic potential. Haemolysis testing demonstrated that Au@Pt NPs are biocompatible and fluorescent microscopy confirmed their entering the cells. Cytological evaluation of the NPs through MTT assay showed that they do not inhibit the proliferation of control cell line HEK293, whereas they are toxic in U87MG, U251 and D54 glioblastoma cell lines; rendering them selective targeting agents for treating glioblastoma.


Assuntos
Glioblastoma , Nanopartículas Metálicas , Sistemas de Liberação de Medicamentos , Glioblastoma/tratamento farmacológico , Ouro/química , Células HEK293 , Humanos , Nanopartículas Metálicas/química , Platina/química
10.
Adv Healthc Mater ; 11(7): e2101544, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34706167

RESUMO

Prostate cancer (PCa), one of the leading causes of cancer-related deaths, currently lacks effective treatment for advanced-stage disease. Paclitaxel (PTX) is a highly active chemotherapeutic drug and the first-line treatment for PCa; however, conventional PTX formulation causes severe hypersensitivity reactions and limits PTX use at high concentrations. In the pursuit of high molecular weight, biodegradable, and pH-responsive polymeric carriers, one conjugates PTX to a polyacetal-based nanocarrier to yield a tert-Ser-PTX polyacetal conjugate. tert-Ser-PTX conjugate provides sustained release of PTX over 2 weeks in a pH-responsive manner while also obtaining a degree of epimerization of PTX to 7-epi-PTX. Serum proteins stabilize tert-Ser-PTX, with enhanced stability in human serum versus PBS (pH 7.4). In vitro efficacy assessments in PCa cells demonstrate IC50 values above those for the free form of PTX due to the differential cell trafficking modes; however, in vivo tolerability assays demonstrate that tert-Ser-PTX significantly reduces the systemic toxicities associated with free PTX treatment. tert-Ser-PTX also effectively inhibits primary tumor growth and hematologic, lymphatic, and coelomic dissemination, as confirmed by in vivo and ex vivo bioluminescence imaging and histopathological evaluations in mice carrying orthotopic LNCaP tumors. Overall, the results suggest the application of tert-Ser-PTX as a robust antitumor/antimetastatic treatment for PCa.


Assuntos
Antineoplásicos Fitogênicos , Neoplasias da Próstata , Acetais , Animais , Antineoplásicos Fitogênicos/uso terapêutico , Linhagem Celular Tumoral , Portadores de Fármacos/química , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Paclitaxel/química , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Polímeros/química , Neoplasias da Próstata/tratamento farmacológico
11.
Am J Pathol ; 176(1): 330-42, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19948825

RESUMO

Hippocampal sclerosis is a common pathological finding in patients with temporal lobe epilepsy, including children, but a causal relationship to early-life seizures remains in question. Neonatal status epilepticus in animals can result in neuronal death within the hippocampus, although macroscopic features of hippocampal shrinkage are not evident at adulthood. Here, we examined electrophysiological and pathological consequences of focally evoked status epilepticus triggered by intra-amygdala microinjection of kainic acid in postnatal day 10 rat pups. Neonatal status epilepticus resulted in extensive neuronal death in the ipsilateral hippocampal CA1 and CA3 subfields and hilus, as assessed by DNA fragmentation and Fluoro-Jade B staining 72 hours later. The contralateral hippocampus was not significantly damaged. Histopathology at P55/P65 revealed unilateral hippocampal sclerosis (grade IV, modified Wyler/Watson scale) comprising >50% CA1 and CA3 neuron loss and astrogliosis. Additional features included hydrocephalus ex vacuo, modest dentate granule cell layer widening, and altered neuropeptide Y immunoreactivity indicative of synaptic rearrangement. Hippocampal atrophy was also evident on magnetic resonance imaging. Depth electrode recordings at adulthood detected spontaneous seizures that involved the ipsilateral hippocampus and amygdala. A significant positive correlation was found between hippocampal pathology grade and both frequency and duration of epileptic seizures at adulthood. The current study demonstrates that experimental neonatal status epilepticus can result in classical unilateral hippocampal sclerosis and temporal lobe epilepsy.


Assuntos
Epilepsia do Lobo Temporal/complicações , Hipocampo/patologia , Estado Epiléptico/complicações , Envelhecimento/patologia , Tonsila do Cerebelo/patologia , Animais , Animais Recém-Nascidos , Morte Celular , Forma Celular , Eletroencefalografia , Epilepsia do Lobo Temporal/patologia , Feminino , Hipocampo/metabolismo , Imageamento por Ressonância Magnética , Masculino , Neurônios/patologia , Neuropeptídeo Y/metabolismo , Fenótipo , Ratos , Ratos Sprague-Dawley , Esclerose , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/patologia
12.
Mol Pharm ; 8(5): 1887-98, 2011 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-21882837

RESUMO

For therapeutic peptides, the lung represents an attractive, noninvasive route into the bloodstream. To achieve optimal bioavailability and control their fast rate of absorption, peptides can be protected by coprocessing with polymers such as polyethylene glycol (PEG). Here, we formulated and characterized salmon calcitonin (sCT)-loaded microparticles using linear or branched PEG (L-PEG or B-PEG) and hydroxypropyl-beta-cyclodextrin (HPßCD) for pulmonary administration. Mixtures of sCT, L-PEG or B-PEG and HPßCD were co-spray dried. Based on the particle properties, the best PEG:HPßCD ratio was 1:1 w:w for both PEGs. In the sCT-loaded particles, the L-PEG was more crystalline than B-PEG. Thus, L-PEG-based particles had lower surface free energy and better aerodynamic behavior than B-PEG-based particles. However, B-PEG-based particles provided better protection against chemical degradation of sCT. A decrease in sCT permeability, measured across Calu-3 bronchial epithelial monolayers, occurred when the PEG and HPßCD concentrations were both 1.6 wt %. This was attributed to an increase in buffer viscosity, caused by the two excipients. sCT pharmacokinetic profiles in Wistar rats were evaluated using a 2-compartment model after iv injection or lung insufflation. The maximal sCT plasma concentration was reached within 3 min following nebulization of sCT solution. L-PEG and B-PEG-based microparticles were able to increase T(max) to 20 ± 1 min and 18 ± 8 min, respectively. Furthermore, sCT absolute bioavailability after L-PEG-based microparticle aerosolization at 100 µg/kg was 2.3 times greater than for the nebulized sCT solution.


Assuntos
Conservadores da Densidade Óssea/administração & dosagem , Brônquios/metabolismo , Calcitonina/administração & dosagem , Sistemas de Liberação de Medicamentos , Polietilenoglicóis/química , Mucosa Respiratória/metabolismo , beta-Ciclodextrinas/química , 2-Hidroxipropil-beta-Ciclodextrina , Animais , Disponibilidade Biológica , Transporte Biológico , Conservadores da Densidade Óssea/sangue , Conservadores da Densidade Óssea/metabolismo , Conservadores da Densidade Óssea/farmacocinética , Calcitonina/sangue , Calcitonina/metabolismo , Calcitonina/farmacocinética , Linhagem Celular , Fenômenos Químicos , Química Farmacêutica , Estabilidade de Medicamentos , Proteínas de Peixes/administração & dosagem , Proteínas de Peixes/sangue , Proteínas de Peixes/metabolismo , Proteínas de Peixes/farmacocinética , Meia-Vida , Masculino , Teste de Materiais , Tamanho da Partícula , Ratos , Ratos Wistar
13.
Nanomaterials (Basel) ; 11(10)2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34685073

RESUMO

Nanotheranostics constitute a novel drug delivery system approach to improving systemic, brain-targeted delivery of diagnostic imaging agents and pharmacological moieties in one rational carrier platform. While there have been notable successes in this field, currently, the clinical translation of such delivery systems for the treatment of neurological disorders has been limited by the inadequacy of correlating in vitro and in vivo data on blood-brain barrier (BBB) permeation and biocompatibility of nanomaterials. This review aims to identify the most contemporary non-invasive approaches for BBB crossing using nanotheranostics as a novel drug delivery strategy and current non-animal-based models for assessing the safety and efficiency of such formulations. This review will also address current and future directions of select in vitro models for reducing the cumbersome and laborious mandate for testing exclusively in animals. It is hoped these non-animal-based modelling approaches will facilitate researchers in optimising promising multifunctional nanocarriers with a view to accelerating clinical testing and authorisation applications. By rational design and appropriate selection of characterised and validated models, ranging from monolayer cell cultures to organ-on-chip microfluidics, promising nanotheranostic particles with modular and rational design can be screened in high-throughput models with robust predictive power. Thus, this article serves to highlight abbreviated research and development possibilities with clinical translational relevance for developing novel nanomaterial-based neuropharmaceuticals for therapy in CNS disorders. By generating predictive data for prospective nanomedicines using validated in vitro models for supporting clinical applications in lieu of requiring extensive use of in vivo animal models that have notable limitations, it is hoped that there will be a burgeoning in the nanotherapy of CNS disorders by virtue of accelerated lead identification through screening, optimisation through rational design for brain-targeted delivery across the BBB and clinical testing and approval using fewer animals. Additionally, by using models with tissue of human origin, reproducible therapeutically relevant nanomedicine delivery and individualised therapy can be realised.

14.
Nanotoxicology ; 15(9): 1151-1167, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34752713

RESUMO

This article presents an automated image-processing workflow for quantitative assessment of SPION accumulation in tissue sections stained with Prussian blue for iron detection. We utilized supervised machine learning with manually labeled features used for training the classifier. Performance of the classifier was validated by 10-fold cross-validation of obtained data and by measuring Dice and Jaccard Similarity Coefficients between manually segmented image and automated segmentation. The proposed approach provides time and cost-effective solution for quantitative imaging analysis of SPION in tissue with a precision similar to that obtained via thresholding method for stain quantification. Furthermore, we exploited the classifiers to generate segmented 3D volumes from histological slides. This enabled visualization of particles which were obscured in original 3D histology stacks. Our approach offers a powerful tool for preclinical assessment of the precise tissue-specific SPION biodistribution, which could affect both their toxicity and their efficacy as nanocarriers for medicines.


Assuntos
Processamento de Imagem Assistida por Computador , Nanopartículas Magnéticas de Óxido de Ferro , Processamento de Imagem Assistida por Computador/métodos , Distribuição Tecidual
15.
Acta Biomater ; 121: 89-102, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33227487

RESUMO

The treatment for glioblastoma multiforme (GBM) has not changed for more than 20 years while the prognosis for the patients is still poor and most of them survive less than 1 year after diagnosis. The standard of care for GBM is comprised of surgical resection followed by radiotherapy and oral chemotherapy with temozolomide. The placement of carmustine wafers in the brain after tumour removal is added in cases of recurrent glioma. Significant research is underway to improve the GBM therapy outcome and patient quality of life. Biomaterials are in the front line of the research focus for new treatment options. Specially, biocompatible polymers have been proposed in hydrogel-based formulations aiming at injectable and localized therapies. These formulations can comprise many different pharmacological agents such as chemotherapeutic drugs, nanoparticles, cells, nucleic acids, and diagnostic agents. In this manuscript, we review the most recent formulations developed and tested both in vitro and in vivo using different types of hydrogels. Firstly, we describe three common types of thermo-responsive polymers addressing the advantages and drawbacks of their formulations. Then, we focus on formulations specifically developed for GBM treatment.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Neoplasias Encefálicas/tratamento farmacológico , Carmustina , Glioblastoma/tratamento farmacológico , Humanos , Recidiva Local de Neoplasia , Polímeros , Qualidade de Vida
16.
Nanomaterials (Basel) ; 8(5)2018 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-29734795

RESUMO

Magnetic nanoparticle (MNP)-mediated hyperthermia (MH) coupled with radiation therapy (RT) is a novel approach that has the potential to overcome various practical difficulties encountered in cancer treatment. In this work, we present recommendations for the in vitro and in vivo testing and application of the two treatment techniques. These recommendations were developed by the members of Working Group 3 of COST Action TD 1402: Multifunctional Nanoparticles for Magnetic Hyperthermia and Indirect Radiation Therapy ("Radiomag"). The purpose of the recommendations is not to provide definitive answers and directions but, rather, to outline those tests and considerations that a researcher must address in order to perform in vitro and in vivo studies. The recommendations are divided into 5 parts: (a) in vitro evaluation of MNPs; (b) in vitro evaluation of MNP-cell interactions; (c) in vivo evaluation of the MNPs; (d) MH combined with RT; and (e) pharmacokinetic studies of MNPs. Synthesis and characterization of the MNPs, as well as RT protocols, are beyond the scope of this work.

18.
ACS Appl Mater Interfaces ; 8(2): 1164-75, 2016 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-26692360

RESUMO

Amorphous calcium carbonate (ACC) is known to interact with proteins, for example, in biogenic ACC, to form stable amorphous phases. The control of amorphous/crystalline and inorganic/organic ratios in inhalable calcium carbonate microparticles may enable particle properties to be adapted to suit the requirements of dry powders for pulmonary delivery by oral inhalation. For example, an amorphous phase can immobilize and stabilize polypeptides in their native structure and amorphous and crystalline phases have different mechanical properties. Therefore, inhalable composite microparticles made of inorganic (i.e., calcium carbonate and calcium formate) and organic (i.e., hyaluronan (HA)) amorphous and crystalline phases were investigated for peptide and protein pulmonary aerosol delivery. The crystalline/amorphous ratio and polymorphic form of the inorganic component was altered by changing the microparticle drying rate and by changing the ammonium carbonate and HA initial concentration. The bioactivity of the model peptide, salmon calcitonin (sCT), coprocessed with alpha-1-antitrypsin (AAT), a model protein with peptidase inhibitor activity, was maintained during processing and the microparticles had excellent aerodynamic properties, making them suitable for pulmonary aerosol delivery. The bioavailability of sCT after aerosol delivery as sCT and AAT-loaded composite microparticles to rats was 4-times higher than that of sCT solution.


Assuntos
Carbonato de Cálcio/química , Pneumopatias/tratamento farmacológico , Nanopartículas/química , Peptídeos/química , Administração por Inalação , Aerossóis/química , Aerossóis/uso terapêutico , Animais , Calcitonina/administração & dosagem , Calcitonina/química , Carbonato de Cálcio/administração & dosagem , Humanos , Pneumopatias/patologia , Nanopartículas/administração & dosagem , Tamanho da Partícula , Peptídeos/administração & dosagem , Ratos , alfa 1-Antitripsina/administração & dosagem , alfa 1-Antitripsina/química
19.
Theranostics ; 5(11): 1249-63, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26379790

RESUMO

In a report from 2008, The International Agency for Research on Cancer predicted a tripled cancer incidence from 1975, projecting a possible 13-17 million cancer deaths worldwide by 2030. While new treatments are evolving and reaching approval for different cancer types, the main prevention of cancer mortality is through early diagnosis, detection and treatment of malignant cell growth. The last decades have seen a development of new imaging techniques now in widespread clinical use. The development of nano-imaging through fluorescent imaging and magnetic resonance imaging (MRI) has the potential to detect and diagnose cancer at an earlier stage than with current imaging methods. The characteristic properties of nanoparticles result in their theranostic potential allowing for simultaneous detection of and treatment of the disease. This review provides state of the art of the nanotechnological applications for cancer therapy. Furthermore, it advances a novel concept of personalized nanomedical theranostic therapy using iron oxide magnetic nanoparticles in conjunction with MRI imaging. Regulatory and industrial perspectives are also included to outline future perspectives in nanotechnological cancer research.


Assuntos
Portadores de Fármacos/administração & dosagem , Magnetismo , Nanopartículas/administração & dosagem , Neoplasias/diagnóstico , Neoplasias/tratamento farmacológico , Nanomedicina Teranóstica/métodos , Compostos Férricos/administração & dosagem , Imagem Óptica/métodos , Imagem Óptica/tendências , Medicina de Precisão/métodos , Medicina de Precisão/tendências
20.
Nanomedicine (Lond) ; 10(11): 1751-60, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26080697

RESUMO

AIM: Superparamagnetic iron oxide nanoparticles (SPIONs) may play an important role in nanomedicine by serving as drug carriers and imaging agents. In this study, we present the biodistribution and pharmacokinetic properties of SPIONs using a new detection method, particle electron paramagnetic resonance (pEPR). MATERIALS & METHODS: The pEPR technique is based on a low-field and low-frequency electron paramagnetic resonance. pEPR was compared with inductively coupled plasma mass spectrometry and MRI, in in vitro and in vivo. RESULTS: The pEPR, inductively coupled plasma mass spectrometry and MRI results showed a good correlation between the techniques. CONCLUSION: The results indicate that pEPR can be used to detect SPIONs in both preclinical and clinical studies.


Assuntos
Compostos Férricos/administração & dosagem , Nanomedicina , Nanopartículas/administração & dosagem , Animais , Meios de Contraste/administração & dosagem , Meios de Contraste/química , Espectroscopia de Ressonância de Spin Eletrônica , Compostos Férricos/análise , Humanos , Imageamento por Ressonância Magnética , Nanopartículas/análise , Ratos , Distribuição Tecidual
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