Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 76
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Eur J Nucl Med Mol Imaging ; 49(1): 110-124, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34783879

RESUMO

PURPOSE: Translocator protein 18-kDa (TSPO) positron emission tomography (PET) is a valuable tool to detect neuroinflammed areas in a broad spectrum of neurodegenerative diseases. However, the clinical application of second-generation TSPO ligands as biomarkers is limited because of the presence of human rs6971 polymorphism that affects their binding. Here, we describe the ability of a new TSPO ligand, [18F]BS224, to identify abnormal TSPO expression in neuroinflammation independent of the rs6971 polymorphism. METHODS: An in vitro competitive inhibition assay of BS224 was conducted with [3H]PK 11195 using membrane proteins isolated from 293FT cells expressing TSPO-wild type (WT) or TSPO-mutant A147T (Mut), corresponding to a high-affinity binder (HAB) and low-affinity binder (LAB), respectively. Molecular docking was performed to investigate the interaction of BS224 with the binding sites of rat TSPO-WT and TSPO-Mut. We synthesized a new 18F-labeled imidazopyridine acetamide ([18F]BS224) using boronic acid pinacol ester 6 or iodotoluene tosylate precursor 7, respectively, via aromatic 18F-fluorination. Dynamic PET scanning was performed up to 90 min after the injection of [18F]BS224 to healthy mice, and PET imaging data were obtained to estimate its absorbed doses in organs. To evaluate in vivo TSPO-specific uptake of [18F]BS224, lipopolysaccharide (LPS)-induced inflammatory and ischemic stroke rat models were used. RESULTS: BS224 exhibited a high affinity (Ki = 0.51 nM) and selectivity for TSPO. The ratio of IC50 values of BS224 for LAB to that for HAB indicated that the TSPO binding affinity of BS224 has low binding sensitivity to the rs6971 polymorphism and it was comparable to that of PK 11195, which is not sensitive to the polymorphism. Docking simulations showed that the binding mode of BS224 is not affected by the A147T mutation and consequently supported the observed in vitro selectivity of [18F]BS224 regardless of polymorphisms. With optimal radiochemical yield (39 ± 6.8%, decay-corrected) and purity (> 99%), [18F]BS224 provided a clear visible image of the inflammatory lesion with a high signal-to-background ratio in both animal models (BPND = 1.43 ± 0.17 and 1.57 ± 0.37 in the LPS-induced inflammatory and ischemic stroke rat models, respectively) without skull uptake. CONCLUSION: Our results suggest that [18F]BS224 may be a promising TSPO ligand to gauge neuroinflammatory disease-related areas in a broad range of patients irrespective of the common rs6971 polymorphism.


Assuntos
Tomografia por Emissão de Pósitrons , Receptores de GABA , Animais , Proteínas de Transporte , Humanos , Ligantes , Camundongos , Simulação de Acoplamento Molecular , Compostos Radiofarmacêuticos , Ratos , Receptores de GABA/genética , Receptores de GABA/metabolismo , Receptores de GABA-A
2.
Int J Mol Sci ; 21(19)2020 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-32992469

RESUMO

The development of medicines designed for children can be challenging since this distinct patient population requires specific needs. A formulation designed for paediatric patients must consider the following aspects: patient population variability; dose flexibility; route of administration; patient compliance; drug and excipient tolerability. The purpose of this Special Issue entitled "Paediatric Formulation: Design and Development" is to provide an update on both state-of-the-art methodology and operational challenges in the design and development of paediatric formulations. It aims at re-evaluating what is needed for more progress in the design and development of age-appropriate treatments for paediatric diseases, focusing on: formulation development; drug delivery design; efficacy, safety, and tolerability of drugs and excipients. This editorial, briefly, summarizes the objects of nine original research and review papers published in this Special Issue.


Assuntos
Química Farmacêutica , Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Desenvolvimento de Medicamentos , Criança , Excipientes/química , Excipientes/uso terapêutico , Humanos , Publicações Periódicas como Assunto
3.
Int J Mol Sci ; 21(12)2020 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-32586039

RESUMO

The therapeutic approach to Chronic Myeloid Leukemia (CML) has changed since the advent of the tyrosine kinase inhibitor (TKI) imatinib, which was then followed by the second generation TKIs dasatinib, nilotinib, and, finally, by ponatinib, a third-generation drug. At present, these therapeutic options represent the first-line treatment for adults. Based on clinical experience, imatinb, dasatinib, and nilotinib have been approved for children even though the studies that were concerned with efficacy and safety toward pediatric patients are still awaiting more specific and high-quality data. In this scenario, it is of utmost importance to prospectively validate data extrapolated from adult studies to set a standard therapeutic management for pediatric CML by employing appropriate formulations on the basis of pediatric clinical trials, which allow a careful monitoring of TKI-induced adverse effects especially in growing children exposed to long-term therapy.


Assuntos
Proteínas de Fusão bcr-abl/antagonistas & inibidores , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Criança , Proteínas de Fusão bcr-abl/genética , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Prognóstico
4.
Int J Mol Sci ; 21(18)2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32906812

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive malignancies, with poor outcomes largely due to its unique microenvironment, which is responsible for the low response to drugs and drug-resistance phenomena. This clinical need led us to explore new therapeutic approaches for systemic PDAC treatment by the utilization of two newly synthesized biphenylnicotinamide derivatives, PTA73 and PTA34, with remarkable antitumor activity in an in vitro PDAC model. Given their poor water solubility, inclusion complexes of PTA34 and PTA73 in Hydroxy-Propil-ß-Cyclodextrin (HP-ß-CD) were prepared in solution and at the solid state. Complexation studies demonstrated that HP-ß-CD is able to form stable host-guest inclusion complexes with PTA34 and PTA73, characterized by a 1:1 apparent formation constant of 503.9 M-1 and 369.2 M-1, respectively (also demonstrated by the Job plot), and by an increase in aqueous solubility of about 150 times (from 1.95 µg/mL to 292.5 µg/mL) and 106 times (from 7.16 µg/mL to 762.5 µg/mL), in the presence of 45% w/v of HP-ß-CD, respectively. In vitro studies confirmed the high antitumor activity of the complexed PTA34 and PTA73 towards PDAC cells, the strong G2/M phase arrest followed by induction of apoptosis, and thus their eligibility for PDAC therapy.


Assuntos
2-Hidroxipropil-beta-Ciclodextrina/química , 2-Hidroxipropil-beta-Ciclodextrina/farmacologia , Compostos de Bifenilo/farmacologia , Compostos de Bifenilo/química , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/metabolismo , Linhagem Celular Tumoral/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Química Farmacêutica/métodos , Composição de Medicamentos/métodos , Humanos , Corpos de Inclusão/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Microambiente Tumoral/efeitos dos fármacos , Difração de Raios X/métodos , beta-Ciclodextrinas/metabolismo , beta-Ciclodextrinas/farmacologia
5.
Int J Mol Sci ; 20(3)2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-30704045

RESUMO

New scientific findings have recently shown that dasatinib (DAS), the first-choice oral drug in the treatment of chronic myeloid leukemia (CML) for adult patients who are resistant or intolerant to imatinib, is also potentially useful in the paediatric age. Moreover, recent preclinical evidences suggest that this drug could be useful for the treatment of Duchenne muscular dystrophy, since it targets cSrc tyrosin kinase. Based on these considerations, the purpose of this work was to use the strategy of complexation with hydroxypropyl-ß-cyclodextrin (HP-ß-CD) in order to obtain an aqueous preparation of DAS, which is characterized by a low water solubility (6.49 × 10-4 mg/mL). Complexation studies demonstrated that HP-ß-CD is able to form a stable host-guest inclusion complex with DAS with a 1:1 apparent formation constant of 922.13 M-1, as also demonstrated by the Job's plot, with an increase in DAS aqueous solubility of about 21 times in the presence of 6% w/v of HP-ß-CD (0.014 mg/mL). The inclusion complex has been prepared in the solid state by lyophilization and characterized by Fourier Transform Infrared (FT-IR), Nuclear Magnetic Resonance (NMR), Differential Scanning Calorimetry (DSC) techniques, and its dissolution profile was studied at different pH values. Moreover, in view of potential use of DAS for Duchenne muscular dystrophy, the cytotoxic effect of the inclusion complex has been assessed on C2C12 cells, a murine muscle satellite cell line. In parallel, a one-week oral treatment was performed in wild type C57Bl/6J mice to test both palatability and the exposure levels of the new oral formulation of the compound. In conclusion, this new inclusion complex could allow the development of a liquid and solvent free formulation to be administered both orally and parenterally, especially in the case of an administration in paediatric age.


Assuntos
2-Hidroxipropil-beta-Ciclodextrina/química , Dasatinibe/química , Doenças Neuromusculares/tratamento farmacológico , Animais , Varredura Diferencial de Calorimetria , Linhagem Celular , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Distrofia Muscular de Duchenne , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier
6.
Int J Mol Sci ; 20(8)2019 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-30999610

RESUMO

Autoinflammatory diseases (AIDs) are heterogeneous disorders characterized by dysregulation in the inflammasome, a large intracellular multiprotein platform, leading to overproduction of interleukin-1(IL-1)ß that plays a predominant pathogenic role in such diseases. Appropriate treatment is crucial, also considering that AIDs may persist into adulthood with negative consequences on patients' quality of life. IL-1ß blockade results in a sustained reduction of disease severity in most AIDs. A growing experience with the human IL-1 receptor antagonist, Anakinra (ANA), and the monoclonal anti IL-1ß antibody, Canakinumab (CANA), has also been engendered, highlighting their efficacy upon protean clinical manifestations of AIDs. Safety and tolerability have been confirmed by several clinical trials and observational studies on both large and small cohorts of AID patients. The same treatment has been proposed in refractory Kawasaki disease, an acute inflammatory vasculitis occurring in children before 5 years, which has been postulated to be autoinflammatory for its phenotypical and immunological similarity with systemic juvenile idiopathic arthritis. Nevertheless, minor concerns about IL-1 antagonists have been raised regarding their employment in children, and the development of novel pharmacological formulations is aimed at minimizing side effects that may affect adherence to treatment. The present review summarizes current findings on the efficacy, safety, and tolerability of ANA and CANA for treatment of AIDs and Kawasaki vasculitis with a specific focus on the pediatric setting.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Artrite Juvenil/tratamento farmacológico , Síndromes Periódicas Associadas à Criopirina/tratamento farmacológico , Febre Familiar do Mediterrâneo/tratamento farmacológico , Febre/tratamento farmacológico , Doenças Hereditárias Autoinflamatórias/tratamento farmacológico , Proteína Antagonista do Receptor de Interleucina 1/uso terapêutico , Deficiência de Mevalonato Quinase/tratamento farmacológico , Síndrome de Linfonodos Mucocutâneos/tratamento farmacológico , Animais , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais Humanizados , Artrite Juvenil/imunologia , Síndromes Periódicas Associadas à Criopirina/imunologia , Febre Familiar do Mediterrâneo/imunologia , Febre/imunologia , Doenças Hereditárias Autoinflamatórias/imunologia , Humanos , Proteína Antagonista do Receptor de Interleucina 1/efeitos adversos , Interleucina-1beta/imunologia , Deficiência de Mevalonato Quinase/imunologia , Síndrome de Linfonodos Mucocutâneos/imunologia , Receptores de Interleucina-1/antagonistas & inibidores
7.
Int J Mol Sci ; 19(1)2018 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-29342117

RESUMO

Overexpression of the 18-kDa translocator protein (TSPO) is closely linked to inflammatory responses in the heart, including myocarditis, which can lead to myocardial necrosis. In vivo assessment of inflammatory responses has enabled the precise diagnosis of myocarditis to improve clinical outcomes. Here, we evaluated TSPO overexpression in a rat model of experimental autoimmune myocarditis (EAM) compared to healthy rats using two TSPO radiotracers, [18F]fluoromethyl-PBR28 ([18F]1) and [18F]CB251 ([18F]2). All radiolabeling methods were successfully applied to an automated module for the reproducible preparation of TSPO radiotracers. Both radiotracers were directly compared in an EAM rat model, as well as in healthy rats to determine whether either radiotracer provides a more promising assessment of in vivo TSPO overexpression. [18F]2 provided more specific TSPO-uptake in the heart of the EAM rats (1.32-fold that of the heart-to-lung uptake ratio versus healthy controls), while [18F]1 did not show a significant difference between the two groups. Histopathological characterization revealed that a prominent positron emission tomography (PET) signal of [18F]2 in the EAM rats corresponded to the presence of a higher density of TSPO compared to the healthy controls. These results suggest that the imidazole[1,2-a]pyridine-based radiotracer [18F]2 is a sensitive tool for noninvasively diagnosing myocarditis related to inflammation of the heart muscle by assessing abnormal TSPO expression.


Assuntos
Doenças Autoimunes/genética , Proteínas de Transporte/genética , Expressão Gênica , Miocardite/genética , Receptores de GABA-A/genética , Animais , Doenças Autoimunes/diagnóstico por imagem , Doenças Autoimunes/imunologia , Biomarcadores , Proteínas de Transporte/química , Proteínas de Transporte/metabolismo , Marcação por Isótopo , Masculino , Miocardite/diagnóstico por imagem , Miocardite/imunologia , Tomografia por Emissão de Pósitrons , Traçadores Radioativos , Compostos Radiofarmacêuticos , Ratos , Receptores de GABA-A/química , Receptores de GABA-A/metabolismo
8.
Int J Mol Sci ; 19(4)2018 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-29641449

RESUMO

Translocator protein 18-kDa (TSPO) is a versatile mitochondrial target for molecular imaging and therapy. Moreover, selective TSPO ligands have been widely investigated for diagnostic purposes and explored to target drug delivery systems directed to cancer cells overexpressing TSPO. Indeed, poly(d,l-lactic-co-glycolic acid (PLGA) polymers and nanocarriers decorated with TSPO ligands are capable of transporting TSPO ligands inside cancer cells, inducing survival inhibition in cancer cells and producing mitochondrial morphology modification. The aim of this work was to prepare nanogels (NGs) made with TSPO ligand dextran conjugates (TSPO-Dex) that are useful as potential delivery systems of two TSPO ligands as apoptotic agents. Synthesis and complete characterization of TSPO-dextran conjugates, an average molecular weights analysis, TSPO ligand release profiles, thermal behaviour and swelling studies were achieved. NG preparation, characterization and in vitro biological studies were also performed. The release of TSPO ligands released from dextran conjugates at 37 °C occurred in human serum at a faster rate than that detected in phosphate buffer. Cytotoxicity studies demonstrated that NGs produced from TSPO ligand-dextran conjugates induce survival inhibition in rat C6 glioma cell lines. Cellular uptake was also proven by fluorescence microscopy.


Assuntos
Antineoplásicos/administração & dosagem , Apoptose/efeitos dos fármacos , Dextranos/química , Portadores de Fármacos/síntese química , Hidrogéis/química , Receptores de GABA/metabolismo , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Células Cultivadas , Liberação Controlada de Fármacos , Glioma/metabolismo , Humanos , Ácido Láctico/química , Ligantes , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ligação Proteica , Ratos
9.
Mol Pharm ; 14(9): 3178-3187, 2017 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-28780872

RESUMO

The neurotransmitter dopamine (DA) was covalently linked to oxazepam (OXA), a well-known positive allosteric modulator of γ-aminobutyric acid type-A (GABAA) receptor, through a carbamate linkage (4) or a succinic spacer (6). These conjugates were synthesized with the aim of improving the delivery of DA into the brain and enhancing GABAergic transmission, which may be useful for the long-term treatment of Parkinson disease (PD). Structure-based permeability properties, in vitro stability, and blood-brain barrier (BBB) permeability studies led to identify the OXA-DA carbamate conjugate 4a as the compound better combining sufficient stability and ability to cross BBB. Finally, in vivo microdialysis experiments in freely moving rats demonstrated that 4a (20 mg/kg, i.p.) significantly increases extracellular DA levels into striatum, with a peak (more than 15-fold increase over the baseline) at about 80 min after a single administration. The stability and delivery data proved that 4a may be a promising candidate for further pharmacological studies in animal models of PD.


Assuntos
Corpo Estriado/metabolismo , Dopamina/administração & dosagem , Dopamina/química , Oxazepam/química , Animais , Barreira Hematoencefálica/metabolismo , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Masculino , Doença de Parkinson/metabolismo , Ratos , Ratos Wistar , Ácido gama-Aminobutírico/metabolismo
10.
Pharm Res ; 33(9): 2195-208, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27245467

RESUMO

PURPOSE: Chitosan microparticles containing celecoxib (CB), were developed as chemoprevention of bladder cancer. Furthermore two inclusion complexes of CB with methyl-ß-cyclodextrin (C1 and C2) were prepared to improve the solubility of the drug. METHODS: C1 and C2 were obtained by freeze-drying and characterized in the solid state and in solution. Microparticles loaded with CB or C1 or C2 were prepared by spray drying and fully characterized. RESULTS: The yield and encapsulation efficiencies of microparticles depended by both the viscosity and the presence of the inclusion complex in the feed medium nebulised. Generally, the microparticles exhibited a spherical shape with mean diameter of approximately 2 µm which was compatible with local intravesical administration using a catheter. The CB release studies from the microparticles allowed us to identify both immediate release systems (microparticles including the complexes) and prolonged release systems (microparticles including CB alone). The latter exhibited good adhesion to the bladder mucosa, as highlighted by a mucoadhesion study. Histological studies revealed a desquamation of the superficial cells when the bladder mucosa was treated with microparticles loaded with CB, while the morphology of the urothelium did not change when it was treated with microparticles loaded with the inclusion complex. CONCLUSION: A new CB intravesical formulation than can easily be administered with a catheter and is able to release the drug at the target site for several hours was realized. This new delivery system could be a good alternative to classic oral CB administration.


Assuntos
Celecoxib/química , Quitosana/química , Administração Intravesical , Animais , Celecoxib/administração & dosagem , Química Farmacêutica/métodos , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Liofilização/métodos , Microesferas , Mucosa/metabolismo , Tamanho da Partícula , Solubilidade , Suínos , Bexiga Urinária/metabolismo , Viscosidade , beta-Ciclodextrinas/química
11.
Int J Mol Sci ; 17(6)2016 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-27322261

RESUMO

The 18-kDa translocator protein (TSPO) is a potential mitochondrial target for drug delivery to tumors overexpressing TSPO, including brain cancers, and selective TSPO ligands have been successfully used to selectively deliver drugs into the target. Methotrexate (MTX) is an anticancer drug of choice for the treatment of several cancers, but its permeability through the blood brain barrier (BBB) is poor, making it unsuitable for the treatment of brain tumors. Therefore, in this study, MTX was selected to achieve two TSPO ligand-MTX conjugates (TSPO ligand α-MTX and TSPO ligand γ-MTX), potentially useful for the treatment of TSPO-rich cancers, including brain tumors. In this work, we have presented the synthesis, the physicochemical characterizations, as well as the in vitro stabilities of the new TSPO ligand-MTX conjugates. The binding affinity for TSPO and the selectivity versus central-type benzodiazepine receptor (CBR) was also investigated. The cytotoxicity of prepared conjugates was evaluated on MTX-sensitive human and rat glioma cell lines overexpressing TSPO. The estimated coefficients of lipophilicity and the stability studies of the conjugates confirm that the synthesized molecules are stable enough in buffer solution at pH 7.4, as well in physiological medium, and show an increased lipophilicity compared to the MTX, compatible with a likely ability to cross the blood brain barrier. The latter feature of two TSPO ligand-MTX conjugates was also confirmed by in vitro permeability studies conducted on Madin-Darby canine kidney cells transfected with the human MDR1 gene (MDCK-MDR1) monolayers. TSPO ligand-MTX conjugates have shown to possess a high binding affinity for TSPO, with IC50 values ranging from 7.2 to 40.3 nM, and exhibited marked toxicity against glioma cells overexpressing TSPO, in comparison with the parent drug MTX.


Assuntos
Antineoplásicos/síntese química , Metotrexato/farmacologia , Pró-Fármacos/síntese química , Receptores de GABA/metabolismo , Acetamidas/química , Acetamidas/farmacologia , Animais , Antineoplásicos/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/química , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Linhagem Celular Tumoral , Células Cultivadas , Cães , Humanos , Ligantes , Células Madin Darby de Rim Canino , Metotrexato/química , Pró-Fármacos/farmacologia , Ligação Proteica , Ratos
13.
Drug Dev Ind Pharm ; 41(5): 728-36, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-24650036

RESUMO

New topical totally aqueous formulations that improve the low water solubility of minoxidil and realize an adequate permeability of drug in the skin are proposed. These formulations are lacking in propylene glycol and alcohol that are the principal irritant ingredients present in minoxidil commercial solutions. In order to enhance poor water solubility of minoxidil randomly methyl-ß-cyclodextrin was used, and four hydrogels such as, calcium alginate, sodium alginate, carbopol 934 and hydroxyethylcellulose were utilized to ensure a prolonged time of contact with the scalp. The inclusion complex minoxidil/methyl-ß-cyclodextrin with a molar ratio 1:1 was obtained by freeze drying and evaluated by NMR, FT-IR and DSC analysis. An apparent stability constant of formed inclusion complex was calculated by phase solubility diagram and its value was 400 M(-1). The solid inclusion complex was used to prepare gel formulations with similar dose to minoxidil commercial solution. The gels were evaluated for various technological parameters including rheological behavior, in vitro drug release and ex vivo permeation through pig skin. The best performance was observed for the calcium alginate formulation.


Assuntos
Minoxidil/administração & dosagem , Absorção Cutânea , Vasodilatadores/administração & dosagem , beta-Ciclodextrinas/química , Alopecia/tratamento farmacológico , Animais , Varredura Diferencial de Calorimetria , Química Farmacêutica/métodos , Liberação Controlada de Fármacos , Excipientes/química , Géis , Hidrogéis , Espectroscopia de Ressonância Magnética , Minoxidil/química , Minoxidil/farmacocinética , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Suínos , Vasodilatadores/química , Vasodilatadores/farmacocinética
14.
Mol Pharm ; 11(3): 859-71, 2014 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-24410438

RESUMO

Translocator protein 18 kDa (TSPO) is a promising target for molecular imaging and for targeted drug delivery to tumors overexpressing TSPO. In our previous work, new macromolecular conjugates with a high affinity and selectivity for TSPO were prepared by conjugating the biodegradable poly(d,l-lactic-co-glycolic acid) (PLGA) polymer with two potent and selective TSPO ligands, namely, compounds 1 and 2. Based on this, nanoparticle delivery systems (NPs), employing TSPO ligand-PLGA conjugated (PLGA-TSPO) polymers, were prepared. Furthermore, to evaluate the ability of the new NPs to be used as a drug delivery systems for anticancer therapy, PLGA-TSPO NPs were loaded with 5-fluorouracil (5-FU), chosen as a model hydrophilic anticancer drug. The main goal of this work was to investigate the synergistic potential of using NP conjugates PLGA-TSPO, TSPO ligands being pro-apoptotic agents, to simultaneously deliver a cytotoxic anticancer drug. To better highlight the occurrence of synergistic effects, dual drug loaded PLGA NPs (PLGA NPs/5-FU/1) and dual drug loaded PLGA-TSPO NPs (PLGA-TSPO NPs/5-FU/1), with 5-FU and TSPO ligand 1 physically incorporated together, were also prepared and characterized. The particle size and size distribution, surface morphology, and drug encapsulation efficiency, as well as the drug release kinetics, were investigated. In vitro cytotoxicity studies were carried out on C6 glioma cells overexpressing TSPO, and to evaluate the potential uptake of these nanoparticulate systems, the internalization of fluorescent labeled PLGA-TSPO NPs (FITC-PLGA-TSPO NPs) was also investigated by fluorescence microscopy. Results demonstrated that PLGA-TSPO NPs/5-FU and dual drug loaded PLGA NPs/5-FU/1 and PLGA-TSPO NPs/5-FU/1 could significantly enhance toxicity against human cancer cells due to the synergistic effect of the TSPO ligand 1 with the anticancer drug 5-FU.


Assuntos
Antimetabólitos Antineoplásicos/administração & dosagem , Proteínas de Transporte/metabolismo , Sistemas de Liberação de Medicamentos , Fluoruracila/administração & dosagem , Glioma/tratamento farmacológico , Ácido Láctico/química , Nanopartículas/química , Ácido Poliglicólico/química , Receptores de GABA-A/metabolismo , Antimetabólitos Antineoplásicos/farmacocinética , Apoptose , Varredura Diferencial de Calorimetria , Proteínas de Transporte/administração & dosagem , Proliferação de Células , Portadores de Fármacos , Fluoruracila/farmacocinética , Glioma/metabolismo , Glioma/patologia , Humanos , Microscopia de Fluorescência , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Receptores de GABA-A/administração & dosagem , Distribuição Tecidual , Células Tumorais Cultivadas
15.
Int J Pharm Compd ; 28(2): 151-155, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38604142

RESUMO

This study describes a new method for the preparation of extemporaneous paracetamol-based suspensions for pediatric and adult patients. This method allows the preparation of extemporaneous suspensions up to concentrations of 50 mg/mL by using a liquid base, named "Puccini". A high-pressure liquid chromatographic method was developed and validated for the determination of chemical stability of paracetamol when the formulations were stored at 4°C and 25°C. The chemical stability of the active pharmaceutical ingredient in the base was demonstrated for more than 90 days. Visual analyses of the formulations showed a phenomenon of precipitation at both storage temperatures, but the simple agitation of the formulations before its use re-established the formation of homogeneous suspensions.


Assuntos
Acetaminofen , Adulto , Humanos , Criança , Estabilidade de Medicamentos , Composição de Medicamentos , Suspensões , Administração Oral , Cromatografia Líquida de Alta Pressão , Armazenamento de Medicamentos
16.
Pharmaceutics ; 16(2)2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38399331

RESUMO

Cataract surgery interventions are constantly increasing, particularly among adult and elderly patients. This type of surgery can lead to inflammatory states of the ocular anterior segment (AS), usually healed via postoperative treatment with dexamethasone (DEX)-containing eye drops. The application of eye drops is challenging due to the high number of daily administrations. In this study, mucoadhesive nanoparticles (NPs) were formulated to improve the residence time of DEX on the corneal mucosa, enhancing the drug's solubility and bioavailability. The NPs were generated using an ionotropic gelation technique, exploiting the interaction between the cationic group of chitosan (CS) and the anionic group of sulfobutylether-ß-cyclodextrin (SBE-ß-CD). The formation of the inclusion complex and its stoichiometry were studied through phase solubility studies, Job's plot method, and Bi-directional transport studies on MDCKII-MDR1. The obtained NPs showed good chemical and physical characteristics suitable for drug loading and subsequent testing on animal mucosa. The DEX-loaded CS/SBE-ß-CD NPs exhibited a prolonged residence time on animal mucosa and demonstrated enhanced drug permeability through the corneal membrane, showing a sustained release profile. The developed NPs posed no irritation or toxicity concerns upon local administration, making them an optimal and innovative drug delivery system for inflammatory AS diseases treatment.

17.
Int J Pharm ; 651: 123762, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38185338

RESUMO

Prilling/vibration technique to produce oral microcapsules was explored to achieve local delivery of misoprostol (MIS), a prostaglandin E1 analogue indicated for the treatment of gastric-duodenal ulcers, at the gastric mucosa. To improve MIS chemical stability and reduce its associated systemic side effects, drug delivery systems were designed and developed as microcapsules consisting of a core of sunflower oil and MIS (Fs6 and Fs14) or a MIS complex with hydroxypropyl-beta-cyclodextrin (HP-ß-CD) (Fs18), confirmed by specific studies, and a polymeric shell. The produced microcapsules showed high encapsulation efficiencies for those with MIS solubilized in sunflower oil (>59.86 %) and for the microcapsules with MIS/HP-ß-CD (97.61 %). To demonstrate the ability of these systems to deliver MIS into the stomach, swelling and drug release experiments were also conducted in simulated gastric fluid. Among the three formulations, FS18 showed gastric release within 30 min and was the most advantageous formulation because the presence of the MIS/HP-ß-CD inclusion complex ensured a greater ability to stabilise MIS in the simulated gastric environment. In addition, these new systems have a small size (<540 µm), and good flow properties and the dose of the drug could be easily adapted using different amounts of microcapsules (flexibility), making them a passepartout for different age population groups.


Assuntos
Misoprostol , 2-Hidroxipropil-beta-Ciclodextrina , Cápsulas , Óleo de Girassol , Vibração , Sistemas de Liberação de Medicamentos , Estômago , Solubilidade
18.
Int J Pharm Compd ; 28(1): 68-73, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38306622

RESUMO

Minoxidil is one of the most employed active pharmaceutical ingredients for the  treatment of androgenetic alopecia. The authors propose a new method for production of minoxidil lotions using Aloplus Total. The latter is a propylene glycol-free liquid base in which the presence of hydroxypropyl-ß-cyclodextrin and ethanol allows the solubilization of high drug amounts. Minoxidil intrinsic solubility in the base was determined, and a comprehensive chemical and physical stability study was conducted on 8% w/w minoxidil lotions. Incorporation tests of different active pharmaceutical ingredients that can be combined to 5% w/w minoxidil were also carried out. The analyses showed that minoxidil intrinsic solubility in the new base was 85.93 mg/mL ± 4.17 mg/mL (8.64% w/w ± 0.42% w/w) at 25°C, and the topical lotions were found to be physically and chemically stable for more than 180 days when stored at 25°C or 40°C. Incorporation tests of several active pharmaceutical ingredients also were successful, indicating that Aloplus Total is a liquid vehicle also useful for the preparation of minoxidil-based topical lotions for a synergistic treatment of androgenetic alopecia.


Assuntos
Princípios Ativos , Minoxidil , Humanos , Minoxidil/uso terapêutico , Alopecia/tratamento farmacológico , Solubilidade , Administração Tópica , Resultado do Tratamento
19.
Int J Pharm Compd ; 28(2): 138-145, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38604140

RESUMO

Pharmaceutical compounding has a crucial role for the health of patients, allowing the preparation of formulation out of market or for a personalized therapy. This study is aimed to conduct a screening of possible ready-to-use hydrophilic vehicles for the preparation of topical dosage forms. Incorporation tests of several active pharmaceutical ingredients were performed, and the physical stability of the extemporaneous formulations was assessed by performing an accelerated centrifuge test. The results showed that it was possible to realize several physically stable topical medications without using special equipment or instruments, guaranteeing a fast and repeatable preparation process. The goal of this work is to provide compounding pharmacists a table that summarizes some of the possible vehicles that can be used for the formulation of topical treatments.


Assuntos
Farmacêuticos , Humanos , Composição de Medicamentos/métodos
20.
Int J Pharm Compd ; 28(2): 146-150, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38604141

RESUMO

The preparation of formulations that are not currently on the market or prepared for customized therapy is possible by pharmaceutical compounding. In this study, incorporation tests of some active pharmaceutical ingredients in five ready-touse lipophilic semisolid vehicles were performed, and the physical stability of the prepared extemporaneous formulations was assessed by performing an accelerated centrifuge test. The results demonstrated that it was possible to formulate physically stable topical medications without using special equipment or instruments, ensuring a fast, efficient, and repeatable preparation process. The objective of this work was to provide to compounding pharmacists a table that summarizes some of the semisolid lipophilic vehicles, such as creams water/oil, and ointments, that can be used for the formulation of topical treatments.


Assuntos
Farmacêuticos , Humanos , Composição de Medicamentos/métodos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA