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Schizophrenia is a psychiatric disorder that results from abnormal levels of neurotransmitters in the brain. Risperidone (RIS) is a common drug prescribed for the treatment of schizophrenia. RIS is a hydrophobic drug that is typically administered orally or intramuscularly. Transdermal drug delivery (TDD) could potentially improve the delivery of RIS. This study focused on the development of RIS nanocrystals (NCs), for the first time, which were incorporated into dissolving microneedle array patches (DMAPs) to facilitate the drug delivery of RIS. RIS NCs were formulated via wet-media milling technique using poly(vinylalcohol) (PVA) as a stabiliser. NCs with particle size of 300 nm were produced and showed an enhanced release profile up to 80 % over 28 days. Ex vivo results showed that 1.16 ± 0.04 mg of RIS was delivered to both the receiver compartment and full-thickness skin from NCs loaded DMAPs compared to 0.75 ± 0.07 mg from bulk RIS DMAPs. In an in vivo study conducted using female Sprague Dawley rats, both RIS and its active metabolite 9-hydroxyrisperidone (9-OH-RIS) were detected in plasma samples for 5 days. In comparison with the oral group, DMAPs improved the overall pharmacokinetic profile in plasma with a â¼ 15 folds higher area under the curve (AUC) value. This work has represented the novel delivery of the antipsychotic drug, RIS, through microneedles. It also offers substantial evidence to support the broader application of MAPs for the transdermal delivery of poorly water-soluble drugs.
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Administração Cutânea , Antipsicóticos , Ratos Sprague-Dawley , Risperidona , Esquizofrenia , Animais , Risperidona/administração & dosagem , Risperidona/farmacocinética , Esquizofrenia/tratamento farmacológico , Feminino , Antipsicóticos/administração & dosagem , Antipsicóticos/farmacocinética , Adesivo Transdérmico , Nanopartículas/química , Nanopartículas/administração & dosagem , Liberação Controlada de Fármacos , Absorção Cutânea , Ratos , Sistemas de Liberação de Medicamentos , Pele/metabolismo , Álcool de Polivinil/química , Palmitato de Paliperidona/administração & dosagem , Palmitato de Paliperidona/farmacocinética , Tamanho da Partícula , Solubilidade , AgulhasRESUMO
Quercetin, a natural compound, shows promising potential in wound healing by reducing fibrosis, limiting scar formation, and boosting fibroblast proliferation. However, its effectiveness is hindered by poor solubility, resulting in low bioavailability and necessitating high doses for therapeutic efficacy. This study presents a novel approach, fabricating quercetin-loaded microarray patches (MAPs) using widely employed solubility enhancement strategies. Fabricated MAPs exhibited favourable mechanical strength and could be inserted into excised porcine skin to a depth of 650 µm. Furthermore, formulations containing Soluplus® significantly increased the drug loading capacity, achieving up to 2.5 mg per patch and complete dissolution within an hour of application on excised porcine skin. In vitro studies on full-thickness neonatal porcine skin demonstrated that Soluplus®-enhanced MAPs effectively delivered quercetin across various skin layers, achieving a delivery efficiency exceeding 80% over 24 h. Additionally, these prototype MAPs displayed anti-inflammatory properties and demonstrated biocompatibility with human keratinocyte skin cells. Therefore, quercetin-loaded MAPs employing Soluplus® as a solubility enhancer present a promising alternative strategy for wound healing and anti-inflammatory therapy applications.
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Carbidopa and levodopa remain the established therapeutic standard for managing Parkinson's disease. Nevertheless, their oral administration is hindered by rapid enzymatic degradation and gastrointestinal issues, limiting their efficacy, and necessitating alternative delivery methods. This work presents a novel strategy employing dissolving microarray patches (MAPs) loaded with carbidopa and levodopa, formulated with Tween® 80 to improve their transdermal delivery. The fabricated MAPs demonstrated an acceptable mechanical strength, resisting pressures equivalent to manual human thumb application (32 N) onto the skin. Additionally, these MAPs exhibited an insertion depth of up to 650 µm into excised neonatal porcine skin. Ex vivo dermatokinetic studies could achieve delivery efficiencies of approximately 53.35 % for levodopa and 40.14 % for carbidopa over 24 h, demonstrating their significant potential in drug delivery. Biocompatibility assessments conducted on human dermal fibroblast cells corroborated acceptable cytocompatibility, confirming the suitability of these MAPs for dermal application. In conclusion, dissolving MAPs incorporating carbidopa and levodopa represent a promising alternative for improving the therapeutic management of Parkinson's disease.
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Administração Cutânea , Antiparkinsonianos , Carbidopa , Levodopa , Doença de Parkinson , Carbidopa/administração & dosagem , Levodopa/administração & dosagem , Doença de Parkinson/tratamento farmacológico , Animais , Suínos , Humanos , Antiparkinsonianos/administração & dosagem , Antiparkinsonianos/farmacologia , Adesivo Transdérmico , Pele/metabolismo , Pele/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Absorção Cutânea/efeitos dos fármacos , Combinação de MedicamentosRESUMO
Dissolving microarray patches (DMAPs) represent an innovative approach to minimally invasive transdermal drug delivery, demonstrating efficacy in delivering both small and large therapeutic molecules. However, concerns raised in end-user surveys have hindered their commercialization efforts. One prevalent issue highlighted in these surveys is the lack of clear indicators for successful patch insertion and removal time. To address this challenge, a color-change-based feedback system is devised, which confirms the insertion and dissolution of DMAPs, aiming to mitigate the aforementioned problems. The approach combines hydrophilic needles containing model drugs (fluorescein sodium and fluorescein isothiocyanate (FITC)-dextran) with a hydrophobic poly(lactic acid) baseplate infused with moisture-sensitive silica gel particles. The successful insertion and subsequent complete dissolution of the needle shaft are indicated by the progressive color change of crystal violet encapsulated in the silica. Notably, distinct color alterations on the baseplate, observed 30 min and 1 h after insertion for FITC-dextran and fluorescein sodium DMAPs respectively, signal the full dissolution of the needles, confirming the complete cargo delivery and enabling timely patch removal. This innovative feedback system offers a practical solution for addressing end-user concerns and may significantly contribute to the successful commercialization of DMAPs by providing a visualized drug delivery method.
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Sistemas de Liberação de Medicamentos , Poliésteres , Dióxido de Silício , Dióxido de Silício/química , Poliésteres/química , Sistemas de Liberação de Medicamentos/métodos , Fluoresceína-5-Isotiocianato/química , Fluoresceína-5-Isotiocianato/análogos & derivados , Dextranos/química , Administração Cutânea , Interações Hidrofóbicas e HidrofílicasRESUMO
In a study addressing the high risk of chronic diseases in people with diabetes and obesity linked to metabolic syndrome, the impact of a Golden Berry diet was investigated using a diabetic animal model. Obese rats with diabetic characteristics were fed a diet containing five percent Golden Berry for 16 days. This study focused on various parameters including organ weights, expression of metabolic genes, and urinary biomarkers. Post-Golden Berry intake, there was a notable decrease in the body, liver, pancreas, visceral, and subcutaneous adipose tissue weights in these obese, hyperglycemic rats. In contrast, an increase in brown adipose tissue (BAT) cell mass was observed. This diet also resulted in reduced blood glucose levels and normalized plasma biochemical profiles, including cholesterol, triglycerides, LDL, and HDL levels. Additionally, it modulated specific urinary biomarkers, particularly pipe-colic acid, a primary marker for type 2 diabetes. Bioinformatics analysis linked these dietary effects to improved insulin signaling and adipogenesis. Regular consumption of Golden Berry effectively prevented insulin resistance and obesity in rats, underscoring its significant health benefits and the protective role of an antioxidant-rich diet against metabolic syndrome. These findings offer promising insights for future therapeutic strategies to manage and prevent obesity and related chronic diseases.
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Diabetes Mellitus Tipo 2 , Frutas , Resistência à Insulina , Síndrome Metabólica , Physalis , Animais , Humanos , Ratos , Biomarcadores , Glicemia/metabolismo , Doença Crônica , Dieta Hiperlipídica , Frutas/metabolismo , Insulina , Obesidade/metabolismoRESUMO
Research on the use of microarray patches (MAPs) has progressed at an unprecedented rate over the years, leading to the development of many novel drug delivery systems. As the technology approaches patients, there are several key aspects that ought to be addressed in order to facilitate the smooth translation of MAPs from bench to bedside. One integral factor includes the choice of devices and packaging for the storage of MAPs. In the current work, a slide-and-seal box, MAP-box, was developed for the storage of dissolving MAPs, using fused-deposition modelling. The device has been designed to act as a pill-box for MAPs not only to provide protection for MAPs from the environment, but also to improve patient's adherence to treatment. The overall design of the MAP-box was simple, yet offers the capability of sealing and protecting dissolving MAPs up to 30 days. Donepezil HCl was formulated into a dissolvable MAP, which was used to treat dementia related to Alzheimer's disease. This compound was used as a model formulation to evaluate the utility of the 3D printed MAP-box when placed under three storage conditions: 5 °C and ambient humidity, 25 °C and 65% relative humidity and 40 °C and 75% relative humidity. It was shown that the slide-and-seal box was able to confer protection to MAPs for up to 30 days under accelerated stability study conditions as the drug loading, mechanical properties and insertion properties of MAPs remained unaffected when compared to the unpackaged MAPs stored under these same parameters. These preliminary data provide evidence that the MAP-box prototype may be of great utility for the storage of single or multiple MAPs. Nevertheless, future work will be needed to evaluate their patient usability and its application to different types of MAP systems to fully validate the overall robustness of the prototype.
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Sistemas de Liberação de Medicamentos , Agulhas , Humanos , Administração Cutânea , Adesivo Transdérmico , Impressão TridimensionalRESUMO
The metabolites entering the bloodstream and being excreted in urine as a result of consuming golden berries are currently unidentified. However, these metabolites potentially underlie the health benefits observed in various in vitro, animal, and human models. A nutritional intervention with 18 healthy human volunteers was performed, and urine was collected at baseline and after acute and short-term fruit consumption for 19 days. After UPLC-ESI/QToF-MS analysis, untargeted metabolomics was performed on the urine samples, and from the 50 most discriminant ions (VIP > 2) generated by a validated PLS-DA model (CV-ANOVA = 3.7e-35; R^2Y = 0.86, Q^2Y = 0.62 and no overfitting), 22 compounds were identified with relatively high confidence. The most discriminant metabolites confirmed by DHS/GC-MS2 analysis of volatiles in urine were sesquiterpenes (C15H22): 3 stereoisomers, ß-vatirenene, ß-vetivenene, and ß-vetispirene, and 2 isomers, eremophila-1(10),8,11-triene and α-curcumene. Another major urinary biomarker was 4ß-hydroxywithanolide E and its phase II derivatives, which were observed in urine for all individual up to 24 h after the fruit was consumed; thus, the bioavailability of this biomarker in humans was demonstrated for the first time. Additionally, the excretion of certain acylcarnitines and hypoxanthine in urine increased after golden berry consumption, which may be associated with a detoxifying effect and may occur because fats were utilized rather than carbohydrates to meet the body's energy needs. The main biomarkers of golden berry consumption are specific to this fruit, confirming its potential for the functional food market.
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Frutas , Physalis , Animais , Humanos , Voluntários Saudáveis , Metabolômica , Biomarcadores/urinaRESUMO
Carvedilol, a ß-blocker prescribed for chronic heart failure, suffers from poor bioavailability and rapid first pass metabolism when administered orally. Herein, we present the development of tip microarray patches (MAPs) composed of ternary cyclodextrin (CD) complexes of carvedilol for transdermal delivery. The ternary complex with hydroxypropyl γ-cyclodextrin (HPγCD) and poly(vinyl pyrrolidone) (PVP) reduced the crystallinity of carvedilol, as evidenced by DSC, XRD, NMR, and SEM analysis. MAPs were fabricated using a two-step process with the ternary complex as the needle layer. The resulting MAPs were capable of breaching ex vivo neonatal porcine skin to a depth ≈600 µm with minimal impact to needle height. Upon insertion, the needle dissolved within 2 h, leading to the transdermal delivery of carvedilol. The MAPs displayed minimal toxicity and acceptable biocompatibility in cell assays. In rats, MAPs achieved significantly higher AUC levels of carvedilol than oral administration, with a delayed Tmax and sustained plasma levels over several days. These findings suggest that the carvedilol-loaded dissolving MAPs have the potential to revolutionise the treatment of chronic heart failure.
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Ciclodextrinas , Insuficiência Cardíaca , Suínos , Animais , Ratos , Carvedilol , Administração Oral , Disponibilidade BiológicaRESUMO
Methicillin-resistant Staphylococcus aureus (MRSA) is a prevailing bacterial pathogen linked to superficial skin and soft tissue infections (SSTIs). Rifampicin (RIF), a potent antibiotic against systemic and localised staphylococcal infections, faces limitations due to its low solubility. This constraint hampers its therapeutic potential for MRSA-induced SSTIs. To address this, an advanced liposomal system was designed for efficient dermal RIF delivery. Rifampicin-loaded liposomes (LipoRIF) were embedded within polymeric dissolving microneedles (DMNs) to enable targeted intradermal drug delivery. A robust Design of Experiment (DoE) methodology guided the systematic preparation and optimisation of LipoRIF formulations. The optimal LipoRIF formulation integrated within polymeric DMNs. These LipoRIF-DMNs exhibited favourable mechanical properties and effective skin insertion characteristics. Notably, in vitro assays on skin deposition unveiled a transformative result - the DMN platform significantly enhanced LipoRIF deposition within the skin, surpassing LipoRIF dispersion alone. Moreover, LipoRIF-DMNs displayed minimal cytotoxicity toward cells. Encouragingly, rigorous in vitro antimicrobial evaluations demonstrated LipoRIF-DMNs' capacity to inhibit MRSA growth compared to the control group. LipoRIF-DMNs propose a potentially enhanced, minimally invasive approach to effectively manage SSTIs and superficial skin ailments stemming from MRSA infections.
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Skin and soft tissue infections (SSTIs) arise from microbial ingress into the skin. In this study, poly(2-acrylamido-2-methyl-1-propanesulfonic acid) (polyAMPS), which has been reported to exhibit antimicrobial properties was synthesised for the manufacture of microarray patches (MAPs). The free acid and sodium salt of polyAMPS with controlled molar masses and narrow dispersity were synthesised via reversible addition - fragmentation chain-transfer (RAFT) polymerisation reaction with a monomer conversion of over 99%, as determined by 1H NMR. The polymers were shown to be biocompatible when evaluated using a fibroblast dermal cell line while agar plating assay using cultures of C. albican demonstrated that the acid form of polyAMPS exhibited antimicrobial inhibition, which is potentiated in the presence of antimicrobial agents. The synthesised polymers were then used to fabricate dissolving MAPs, which were loaded with either ITRA or levofloxacin (LEV). The MAPs displayed acceptable mechanical resistance and punctured ex vivo skin to a depth of 600 µm. Skin deposition studies revealed that the MAPs were able to administer up to â¼ 1.9 mg of LEV (delivery efficiency: 94.7%) and â¼ 0.2 mg of ITRA (delivery efficiency: 45.9%), respectively. Collectively, the synthesis and development of this novel pharmaceutical system may offer a strategy to manage SSTIs.
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Anti-Infecciosos , Ácidos Sulfônicos , Antifúngicos/metabolismo , Antibacterianos/metabolismo , Pele/metabolismo , Administração Cutânea , Polímeros/química , Agulhas , Sistemas de Liberação de MedicamentosRESUMO
Obesity is linked to adipose tissue dysfunction, a dynamic endocrine organ. Two-dimensional cultures present technical hurdles hampering their ability to follow individual or cell groups for metabolic disease research. Three-dimensional type I collagen microgels with embedded adipocytes have not been thoroughly investigated to evaluate adipogenic maintenance as instrument for studying metabolic disorders. We aimed to develop a novel tunable Col-I microgel simulating the adipocyte microenvironment to maintain differentiated cells with only insulin as in vitro model for obesity research. Adipocytes were cultured and encapsulated in collagen microgels at different concentrations (2, 3 and 4 mg/mL). Collagen microgels at 3 and 4 mg/mL were more stable after 8 days of culture. However, cell viability and metabolic activity were maintained at 2 and 3 mg/mL, respectively. Cell morphology, lipid mobilization and adipogenic gene expression demonstrated the maintenance of adipocyte phenotype in an in vitro microenvironment. We demonstrated the adequate stability and biocompatibility of the collagen microgel at 3 mg/mL. Cell and molecular analysis confirmed that adipocyte phenotype is maintained over time in the absence of adipogenic factors. These findings will help better understand and open new avenues for research on adipocyte metabolism and obesity. Insight box In the context of adipose tissue dysfunction research, new struggles have arisen owing to the difficulty of cellular maintenance in 2D cultures. Herein, we sought a novel approach using a 3D type I collagen-based biomaterial to adipocyte culture with only insulin. This component was tailored as a microgel in different concentrations to support the growth and survival of adipocytes. We demonstrate that adipocyte phenotype is maintained and key adipogenesis regulators and markers are over time. The cumulative results unveil the practical advantage of this microgel platform as an in vitro model to study adipocyte dysfunction and obesity.
Assuntos
Colágeno Tipo I , Microgéis , Humanos , Adipócitos , Colágeno , Insulina , ObesidadeRESUMO
Three-dimensional matrices are a new strategy used to tackle type I diabetes, a chronic metabolic disease characterized by the destruction of beta pancreatic cells. Type I collagen is an abundant extracellular matrix (ECM), a component that has been used to support cell growth. However, pure collagen possesses some difficulties, including a low stiffness and strength and a high susceptibility to cell-mediated contraction. Therefore, we developed a collagen hydrogel with a poly (ethylene glycol) diacrylate (PEGDA) interpenetrating network (IPN), functionalized with vascular endothelial growth factor (VEGF) to mimic the pancreatic environment for the sustenance of beta pancreatic cells. We analyzed the physicochemical characteristics of the hydrogels and found that they were successfully synthesized. The mechanical behavior of the hydrogels improved with the addition of VEGF, and the swelling degree and the degradation were stable over time. In addition, it was found that 5 ng/mL VEGF-functionalized collagen/PEGDA IPN hydrogels sustained and enhanced the viability, proliferation, respiratory capacity, and functionality of beta pancreatic cells. Hence, this is a potential candidate for future preclinical evaluation, which may be favorable for diabetes treatment.
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Human mesenchymal stem cells (hMSC) represent a unique and promising platform because of their ability to promote soft tissue regeneration, particularly their ability to differentiate into adipocytes, which are important for adipose tissue regeneration. In this context, type I collagen is the most abundant extracellular matrix component of adipose tissue and can act as a natural spheroid source to support the differentiation process of stem cells. However, spheroids based on collagen and hMSCs without numerous pro-adipogenic factors that can induce adipogenesis have not yet been investigated. In this study, we focused on developing collagen-hMSC spheroids capable of differentiating into adipocyte-like cells in a short time (eight culture days) without adipogenic factors, with potential applications in adipose tissue repair. The physical and chemical properties of the spheroids indicated successful cross-linking of collagen. Upon spheroid development, stability, cell viability, and metabolic activity of the constructs were maintained. During adipogenesis, cell morphology shows significant changes, in which cells change from a fibroblast-like shape to an adipocyte-like shape, and adipogenic gene expression after eight days of cell culture. These results support the utility of collagen-hMSC 3 mg ml-1collagen concentration spheroids to differentiate into adipocyte-like cells in a short time without adverse effects on biocompatibility, metabolic activity, or cell morphology, suggesting that this construct may be used in soft tissue engineering.
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Adipogenia , Células-Tronco Mesenquimais , Humanos , Colágeno/farmacologia , Tecido Adiposo , Adipócitos , Diferenciação CelularRESUMO
Obesity is characterized by an expansion of adipose tissue due to excessive accumulation of triglycerides in adipocytes, causing hypertrophy and hyperplasia, followed by hypoxia, alterations in adipocyte functionality, and chronic inflammation. However, current treatments require changes in lifestyle that are difficult to achieve and some treatments do not generate sustained weight loss over time. Therefore, we evaluated the effect of the essential oil (EO) of Lippia alba (Verbenaceae) carvone chemotype on viability, lipid mobilization, and adipogenesis of adipocytes in two normal and pathological cellular models in vitro. In 3T3-L1 adipocytes, a normal and a pathological model of obesity were induced, and then the cells were treated with L. alba carvone chemotype EO to evaluate cell viability, lipid mobilization, and adipogenesis. L. alba carvone chemotype EO does not decrease adipocyte viability at concentrations of 0.1, 1, and 5 µg/mL; furthermore, there was evidence of changes in lipid mobilization and adipogenesis, leading to a reversal of adipocyte hypertrophy. These results could be due to effects produced by EO on lipogenic and lipolytic pathways, as well as modifications in the expression of adipogenesis genes. L. alba carvone chemotype EO could be considered as a possible treatment for obesity, using the adipocyte as a therapeutic target.
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Bacteroides fragilis is one of the most common causative group of microorganisms that is associated with skin and soft tissue infections (SSTI). Metronidazole (MTZ) is the drug of choice used in the treatment of SSTI caused by the bacterium. However, owing to its physiochemical properties, MTZ have limited skin permeation, which render the drug unsuitable for the treatment of deep-rooted SSTIs. One strategy to overcome this limitation is to reformulate MTZ into nanosuspension which will then be loaded into dissolving microarray patches (MAPs) for the treatment of SSTIs caused by B. fragilis. Herein, we report for the first time on the preparation and optimisation of MAP loaded with MTZ nanosuspension (MTZ-NS). After screening a range of polymeric surfactants, we identified that Soluplus® resulted in the formation of MTZ-NS with the smallest particle size (115 nm) and a narrow PDI of 0.27. Next, the MTZ-NS was further optimised using a design of experiments (DoE) approach. The optimised MTZ-NS was then loaded into dissolving MAPs with varying MTZ-NS content. Furthermore, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and cell proliferation assays along with LIVE/DEAD™ staining on the 3T3L1 cell line showed that the MTZ-NS loaded dissolving MAPs displayed minimal toxicity and acceptable biocompatibility. In vitro dermatokinetic studies showed that the MTZ-NS loaded MAPs were able to deliver the nitroimidazole antibiotic across all strata of the skin resulting in a delivery efficiency of 95 % after a 24-hour permeation study. Lastly, agar plating assay using bacterial cultures of B. fragilis demonstrated that MTZ-NS loaded MAP resulted in complete bacterial inhibition in the entire plate relative to the control group. Should this formulation be translated into clinical practice, this pharmaceutical approach may provide a minimally invasive strategy to treat SSTIs caused by B. fragilis.
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Metronidazol , Infecções dos Tecidos Moles , Antibacterianos/farmacologia , Bacteroides fragilis , Humanos , Metronidazol/farmacologia , Preparações Farmacêuticas , Infecções dos Tecidos Moles/tratamento farmacológicoRESUMO
Considered as one of the most common inflammatory arthritis, gout is characterised by a sudden onset of severe joint pain. As the first-line drug of choice used in treating acute gout, colchicine (CLC) is hindered by poor gastrointestinal permeability as well as unfavourable gastrointestinal side effects. Herein, we present, for the first time, the preparation of microarray array patches (MAPs) made of a polymeric solubiliser, Soluplus®, loaded with CLC for its systemic delivery. The fabricated MAPs displayed acceptable mechanical properties and were capable of being inserted into the skin to a depth of ≈500 µm in full thickness ex vivo neonatal porcine skin, as evidenced by optical coherence tomography. In vitro dermatokinetic studies utilising full thickness neonatal porcine skin demonstrated that the CLC-loaded MAPs delivered CLC across all skin strata, resulting in a delivery efficiency of 73% after 24 hours. Furthermore, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and cell proliferation assays along with LIVE/DEAD™ staining on the 3T3-L1 cell line showed that the MAP formulation displayed minimal toxicity, with acceptable biocompatibility. Lastly, the anti-inflammatory properties of the formulation were evaluated using a THP-1 macrophage cell line. It was shown that treatment of THP-1 macrophages that are exposed to lipopolysaccharide (LPS) with CLC-loaded MAPs caused a significant (p < 0.05) reduction of TNF-α production, a pro-inflammatory cytokine typically associated with the early onset of acute gout. Accordingly, CLC-loaded MAPs could represent a new minimally-invasive alternative strategy for management of acute gout.
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Colchicina , Gota , Animais , Colchicina/efeitos adversos , Gota/induzido quimicamente , Gota/tratamento farmacológico , Lipopolissacarídeos , Polietilenoglicóis , Polivinil , Suínos , Fator de Necrose Tumoral alfaRESUMO
In this work the preparation and characterisation of intranasal implants for the delivery of risperidone (RIS) is described. The aim of this work is to develop better therapies to treat chronic conditions affecting the brain such as schizophrenia. This type of systems combines the advantages of intranasal drug delivery with sustained drug release. The resulting implants were prepared using biodegradable materials, including poly(caprolactone) (PCL) and poly(lactic-co-glycolic acid) (PLGA). These polymers were combined with water-soluble compounds, such as poly(ethylene glycol) (PEG) 600, PEG 3000, and Tween® 80 using a solvent-casting method. The resulting implants contained RIS loadings ranging between 25 and 50 %. The obtained implants were characterised using a range of techniques including thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), attenuated total reflectance-Fourier transform infrared (ATR-FTIR), X-ray diffraction (XRD), and Scanning Electron Microscopy (SEM). Moreover, in vitro RIS release was evaluated showing that the addition of water-soluble compounds exhibited significant faster release profiles compared to pristine PCL and PLGA-based implants. Interestingly, PCL-based implants containing 25 % of RIS and PLGA-based implants loaded with 50 % of RIS showed sustained drug release profiles up to 90 days. The former showed faster release rates over the first 28 days but after this period PLGA implants presented higher release rates. The permeability of RIS released from the implants through a model membrane simulating nasal mucosa was subsequently evaluated showing desirable permeation rate of around 2 mg/day. Finally, following in vitro biocompatibility studies, PCL and PLGA-based implants showed acceptable biocompatibility. These results suggested that the resulting implants displayed potential of providing prolonged drug release for brain-targeting drugs.
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Ácido Poliglicólico , Esquizofrenia , Portadores de Fármacos/química , Humanos , Ácido Láctico/química , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Esquizofrenia/tratamento farmacológico , ÁguaRESUMO
Resumen Introducción: La obesidad es considerada un factor de riesgo para desarrollar resistencia a la insulina. La expansión del tejido adiposo se ha relacionado con el aumento de la producción de citoquinas proinflamatorias que, junto a los ácidos grasos son responsables, al menos en parte, del desarrollo de la resistencia a la insulina y esta a su vez, facilita el desarrollo de diabetes mellitus tipo 2 (DMT2). Objetivo: El propósito de este estudio fue realizar y caracterizar un modelo in vitro de obesidad empleando concentraciones altas de glucosa e insulina en una línea de células adipocitarias. Métodos: Se indujo modelo de hipertrofia celular realizando un estímulo en adipocitos maduros con una concentración de glucosa (450 mg/dL) e insulina (106 pmol/L) (modelo HGHI). Tras estímulo se realizaron ensayos de viabilidad celular, diámetro celular, movilización de lípidos y marcadores de señalización de insulina. Resultados: Tras el tratamiento con HGHI, se evidencia hipertrofia adipocitaria, incremento en la acumulación de lípidos, reducción de la ruptura de éstos, alteración de la señalización de insulina y tendencia a modificación de proteínas de marcadores de estrés de retículo y estrés oxidativo. Conclusión: Estos resultados demuestran la validez del modelo in vitro que simula al menos en parte la obesidad asociada a insulino resistencia, siendo una herramienta útil para estudiar los mecanismos de susceptibilidad a obesidad y resistencia a la insulina inducida in vitro con diferentes moléculas.
Abstract Introduction: Obesity is considered a risk factor for developing insulin resistance. The increase in adipose tissue has been related to the increase in the production of pro-inflammatory cytokines, which together with fatty acids are responsible, at least in part, for the development of insulin resistance, and this in turn facilitates the development of T2 diabetes mellitus type 2 (DMT2). Objective: The purpose of this study was to perform and characterize an in vitro model of obesity using high concentrations of glucose and insulin on an adipocyte cell line. Methods: A cell hypertrophy model was induced by stimulating mature adipocytes with a concentration of glucose (450 mg/dL) and insulin (106 pmol/L) (HGHI model). The cell viability, cell diameter, lipid mobilization and insulin signalling markers were evaluated. Results: After HGHI treatment, adipocytes show hypertrophy, increase in lipid accumulation, reduction of lipid breakdown, alteration of insulin signalling, a tendency to modify proteins of reticulum stress markers and, oxidative stress. Conclusion: These results demonstrate a new in vitro model that simulates, at least in part, obesity associated with insulin resistance being a useful tool to study the mechanisms of susceptibility to obesity and insulin resistance induced in vitro by different molecules.