RESUMO
Prior exposure to microenvironmental signals could fundamentally change the response of macrophages to subsequent stimuli. It is believed that T helper-2 (Th2)-cell-type cytokine interleukin-4 (IL-4) and Toll-like receptor (TLR) ligand-activated transcriptional programs mutually antagonize each other, and no remarkable convergence has been identified between them. In contrast, here, we show that IL-4-polarized macrophages established a hyperinflammatory gene expression program upon lipopolysaccharide (LPS) exposure. This phenomenon, which we termed extended synergy, was supported by IL-4-directed epigenomic remodeling, LPS-activated NF-κB-p65 cistrome expansion, and increased enhancer activity. The EGR2 transcription factor contributed to the extended synergy in a macrophage-subtype-specific manner. Consequently, the previously alternatively polarized macrophages produced increased amounts of immune-modulatory factors both in vitro and in vivo in a murine Th2 cell-type airway inflammation model upon LPS exposure. Our findings establish that IL-4-induced epigenetic reprogramming is responsible for the development of inflammatory hyperresponsiveness to TLR activation and contributes to lung pathologies.
Assuntos
Interleucina-4 , Lipopolissacarídeos , Camundongos , Animais , Interleucina-4/metabolismo , Lipopolissacarídeos/metabolismo , Ligantes , Epigenômica , Macrófagos/metabolismo , Receptores Toll-Like/metabolismo , Epigênese Genética , NF-kappa B/metabolismoRESUMO
The emergence of drug-resistant bacteria and fungi represents a serious health problem worldwide. It has long been known that cationic compounds can inhibit the growth of bacteria and fungi by disrupting the cell membrane. The advantage of using such cationic compounds is that the microorganisms would not become resistant to cationic agents, since this type of adaptation would mean significantly altering the structure of their cell walls. We designed novel, DBU (1,8-diazabicyclo[5.4.0]undec-7-ene)-derived amidinium salts of carbohydrates, which may be suitable for disturbing the cell walls of bacteria and fungi due to their quaternary ammonium moiety. A series of saccharide-DBU conjugates were prepared from 6-iodo derivatives of d-glucose, d-mannose, d-altrose and d-allose by nucleophilic substitution reactions. We optimized the synthesis of a d-glucose derivative, and studied the protecting group free synthesis of the glucose-DBU conjugates. The effect of the obtained quaternary amidinium salts against Escherichia coli and Staphylococcus aureus bacterial strains and Candida albicans yeast was investigated, and the impact of the used protecting groups and the sugar configuration on the antimicrobial activity was analyzed. Some of the novel sugar quaternary ammonium compounds with lipophilic aromatic groups (benzyl and 2-napthylmethyl) showed particularly good antifungal and antibacterial activity.
Assuntos
Antifúngicos , Sais , Antifúngicos/farmacologia , Sais/farmacologia , Relação Estrutura-Atividade , Antibacterianos/farmacologia , Fungos , Bactérias , Compostos de Amônio Quaternário/química , Carboidratos/farmacologia , Glucose/farmacologia , Açúcares/farmacologia , Testes de Sensibilidade MicrobianaRESUMO
Increased permeability of the epithelial and endothelial cell layers results in the onset of pathogenic mechanisms. In both cell types, cell-cell connections play a regulatory role in altering membrane permeability. The aim of this study was to investigate the modulating effect of anthocyanin-rich extract (AC) on TJ proteins in inflammatory Caco-2 and HUVEC monolayers. Distribution of Occludin and zonula occludens-1 (ZO-1) were investigated by immunohistochemical staining and the protein levels were measured by flow cytometry. The mRNA expression was determined by quantitative real-time PCR. The transepithelial electrical resistance (TEER) values were measured during a permeability assay on HUVEC cell culture. As a result of inflammatory induction by TNF-α, redistribution of proteins was observed in Caco-2 cell culture, which was reduced by AC treatment. In HUVEC cell culture, the decrease in protein and mRNA expression was more dominant during inflammatory induction, which was compensated for by the AC treatment. Overall, AC positively affected the expression of the examined cell-binding structures forming the membrane on both cell types.
Assuntos
Ocludina , Extratos Vegetais , Prunus avium , Junções Íntimas , Proteína da Zônula de Oclusão-1 , Antocianinas/metabolismo , Células CACO-2 , Humanos , Mucosa Intestinal/metabolismo , Ocludina/genética , Ocludina/metabolismo , Extratos Vegetais/farmacologia , Prunus avium/química , RNA Mensageiro/metabolismo , Junções Íntimas/metabolismo , Proteína da Zônula de Oclusão-1/genética , Proteína da Zônula de Oclusão-1/metabolismoRESUMO
The application of 2-hydroxypropyl-beta-cyclodextrin (HPBCD) in the treatment of the rare cholesterol and lipid storage disorder Niemann-Pick disease type C opened new perspectives in the development of an efficient therapy. Even if the systemic administration of HPBCD was found to be effective, its low permeability across the blood-brain barrier (BBB) limited the positive neurological effects. Nevertheless, the cellular interactions of HPBCD with brain capillary endothelial cells have not been investigated in detail. In this study, the cytotoxicity, permeability, and cellular internalization of HPBCD on primary rat and immortalized human (hCMEC/D3) brain capillary endothelial cells were investigated. HPBCD shows no cytotoxicity on endothelial cells up to 100 µM, measured by impedance kinetics. Using a fluorescent derivative of HPBCD (FITC-HPBCD) the permeability measurements reveal that on an in vitro triple co-culture BBB model, FITC-HPBCD has low permeability, 0.50 × 10-6 cm/s, while on hCMEC/D3 cell layers, the permeability is higher, 1.86 × 10-5 cm/s. FITC-HPBCD enters brain capillary endothelial cells, is detected in cytoplasmic vesicles and rarely localized in lysosomes. The cellular internalization of HPBCD at the BBB can help to develop new strategies for improved HPBCD effects after systemic administration.
Assuntos
Encéfalo , Células Endoteliais , Animais , Humanos , Ratos , 2-Hidroxipropil-beta-Ciclodextrina/farmacologia , Fluoresceína-5-Isotiocianato , Células CultivadasRESUMO
Diabetic retinopathy (DR) is a neurovascular disease characterized by the reduction of retina integrity and functionality, as a consequence of retinal pigment epithelial cell fibrosis. Although galectin-1 (a glycan-binding protein) has been associated with dysregulated retinal angiogenesis, no evidence has been reported about galectin-1 roles in DR-induced fibrosis. ARPE-19 cells were cultured in normal (5 mM) or high glucose (35 mM) for 3 days, then exposed to the selective galectin-1 inhibitor OTX008 (2.5-5-10 µM) for 6 days. The determination of cell viability and ROS content along with the analysis of specific proteins (by immunocytochemistry, Western blotting, and ELISA) or mRNAs (by real time-PCR) were performed. OTX008 5 µM and 10 µM improved cell viability and markedly reduced galectin-1 protein expression in cells exposed to high glucose. This was paralleled by a down-regulation of the TGF-ß/, NF-kB p65 levels, and ROS content. Moreover, epithelial-mesenchymal transition markers were reduced by OTX008 5 µM and 10 µM. The inhibition of galectin-1 by OTX008 in DR may preserve retinal pigment epithelial cell integrity and functionality by reducing their pro-fibrotic phenotype and epithelial-mesenchymal transition phenomenon induced by diabetes.
Assuntos
Retinopatia Diabética , Galectina 1 , Calixarenos , Retinopatia Diabética/metabolismo , Células Epiteliais , Transição Epitelial-Mesenquimal , Fibrose , Glucose/metabolismo , Glucose/farmacologia , Humanos , Fenóis , Espécies Reativas de Oxigênio/metabolismo , Epitélio Pigmentado da Retina/metabolismo , Pigmentos da Retina/metabolismo , Fator de Crescimento Transformador beta/metabolismoRESUMO
Turmeric has been used for decades for its antioxidant and anti-inflammatory effect, which is due to an active ingredient isolated from the plant, called curcumin. However, the extremely poor water-solubility of curcumin often limits the bioavailability of the drug. The aim of our experimental work was to improve the solubility and thus bioavailability of curcumin by developing self-nano/microemulsifying drug delivery systems (SN/MEDDS). Labrasol and Cremophor RH 40 as nonionic surfactants, Transcutol P as co-surfactant and isopropyl myristate as the oily phase were used during the formulation. The average droplet size of SN/MEDDS containing curcumin was between 32 and 405 nm. It was found that the higher oil content resulted in larger particle size. The drug loading efficiency was between 93.11% and 99.12% and all formulations were thermodynamically stable. The curcumin release was studied at pH 6.8, and the release efficiency ranged between 57.3% and 80.9% after 180 min. The results of the MTT cytotoxicity assay on human keratinocyte cells (HaCaT) and colorectal adenocarcinoma cells (Caco-2) showed that the curcumin-containing preparations were non-cytotoxic at 5 w/v%. According to the results of the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and superoxide dismutase (SOD) assays, SNEDDS showed significantly higher antioxidant activity. The anti-inflammatory effect of the SN/MEDDS was screened by enzyme-linked immunosorbent assay (ELISA). SNEDDS formulated with Labrasol as surfactant, reduced tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1ß) levels below 60% at a concentration of 10 w/w%. Our results verified the promising use of SN/MEDDS for the delivery of curcumin. This study demonstrates that the SN/MEDDS could be promising alternatives for the formulation of poorly soluble lipophilic compounds with low bioavailability.
Assuntos
Curcumina , Administração Oral , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Disponibilidade Biológica , Células CACO-2 , Curcumina/química , Curcumina/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Emulsões/química , Excipientes , Humanos , Interleucina-1beta , Óleos/química , Tamanho da Partícula , Solubilidade , Superóxido Dismutase , Tensoativos/química , Fator de Necrose Tumoral alfa , ÁguaRESUMO
Cyclodextrins are high molecular weight, hydrophilic, cyclic, non-reducing oligosaccharides, applied as excipients for the improvement of the solubility and permeability of insoluble active pharmaceutical ingredients. On the other hand, beta-cyclodextrins are used as cholesterol sequestering agents in life sciences. Recently, we demonstrated the cellular internalization and intracellular effects of cyclodextrins on Caco-2 cells. In this study, we aimed to further investigate the endocytosis of (2-hydroxylpropyl)-beta-(HPBCD) and random methylated-beta-cyclodextrin (RAMEB) to test their cytotoxicity, NF-kappa B pathway induction, autophagy, and lysosome formation on HeLa cells. These derivatives were able to enter the cells; however, major differences were revealed in the inhibition of their endocytosis compared to Caco-2 cells. NF-kappa B p65 translocation was not detected in the cell nuclei after HPBCD or RAMEB pre-treatment and cyclodextrin treatment did not enhance the formation of autophagosomes. These cyclodextrin derivates were partially localized in lysosomes after internalization.
Assuntos
Ciclodextrinas , Células CACO-2 , Ciclodextrinas/farmacologia , Excipientes , Células HeLa , Humanos , SolubilidadeRESUMO
Philadelphus coronarius is a versatile plant and its use in folk medicine has a long tradition; however, scientifically, the medical utilization of the herb is a less explored research field. The aim of our study was to identify and determine the quantity of the bioactive compounds of both the leaf and the flower and prepare a lyophilized product of them, from which medical ointments were formulated, since the topical application of P. coronarius has also not been studied. In vitro drug release, texture analysis and biocompatibility experiments were carried out, as well as the investigation of microbiological, antioxidant and anti-inflammatory properties. According to our results the composition and the selected excipients of the ointments have a great impact on the drug release, texture and bioavailability of the preparation. During the microbiological testing, the P. coronarius leaf was effective against Escherichia coli and Staphylococcus aureus, but it did not significantly decrease IL-4 production when it was tested on HaCaT cells. P. coronarius is a promising herb, and its topical application in antimicrobial therapy can be a useful addition to modern medical therapy.
Assuntos
Anti-Infecciosos , Antioxidantes , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Flores , Pomadas , Extratos Vegetais/farmacologia , Folhas de PlantaRESUMO
Fenugreek is used as a spice and a traditional herbal medicine for a variety of purposes, given its antidiabetic and antioxidant effects. Self-emulsifying drug delivery systems (SEDDS) of herbal drugs are targets of extensive research aiming to increase bioavailability and stability. The study's objective was to formulate SEDDS containing Trigonella foenum-graecum extract to improve the stability of herbal extract and to increase their permeability through a Caco-2 monolayer. A characterized fenugreek dry extract was used for the formulations, while the SEDDS properties were examined by particle size analysis and zeta potential measurements. Permeability assays were carried out on Caco-2 cell monolayers, the integrity of which was monitored by follow-up trans-epithelial electric resistance measurements (TEER). Cytocompatibility was tested by the MTT method, and an indirect dissolution test was performed, using DPPH antioxidant reagent. Two different SEDDS compositions were formulated from a standardized fenugreek dry extract at either the micro- or the nanoemulsion scale with sufficient stability, enhanced bioavailability of the compounds, and sustained release from HPMC capsules. Based on our results, a modern, non-toxic, cytocompatible fenugreek SEDDS formulation with high antioxidant capacity was developed in order to improve the permeability and bioavailability of all components.
Assuntos
Trigonella , Antioxidantes/farmacologia , Células CACO-2 , Sistemas de Liberação de Medicamentos/métodos , Humanos , Permeabilidade , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Trigonella/químicaRESUMO
Chrysin (CHR) is a natural flavonoid with a wide range of pharmacological activities, including hepatoprotection, but poor water solubility. By including water-soluble hydroxypropyl (HPBCD) and randomly methylated (RAMEB) ß-cyclodextrin, we aimed to increase its biodisponibility and the effectiveness of the antifibrotic effects of chrysin at oral administration. Liver fibrosis in mice was induced in 7 weeks by CCl4 i.p. administration, and afterwards treated with 50 mg/kg of CHR-HPBCD, CHR-RAMEB, and free chrysin. CCl4 administration increased hepatic inflammation (which was augmented by the upregulation of nuclear factor kappa-light-chain enhancer of activated B cells (NF-kB), tumor necrosis factor (TNF)-α, and interleukin 6 (IL-6) and induced fibrosis, as determined using histopathology and electron microscopy. These results were also confirmed by the upregulation of Collagen I (Col I) and matrix metalloproteinase (MMP) expression, which led to extracellular fibrotic matrix proliferation. Moreover, the immunopositivity of alpha-smooth muscle actin (a-SMA) in the CCl4 group was evidence of hepatic stellate cell (HSC) activation. The main profibrotic pathway was activated, as confirmed by an increase in the transforming growth factor- ß1 (TGF-ß1) and Smad 2/3 expression, while Smad 7 expression was decreased. Treatment with CHR-HPBCD and CHR-RAMEB considerably reduced liver injury, attenuated inflammation, and decreased extracellular liver collagen deposits. CHR-RAMEB was determined to be the most active antifibrotic complex. We conclude that both nanocomplexes exert anti-inflammatory effects and antifibrotic effects in a considerably stronger manner than for free chrysin administration.
Assuntos
Flavonoides/farmacologia , Cirrose Hepática , MicroRNAs/biossíntese , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , beta-Ciclodextrinas/farmacologia , Animais , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/genética , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Masculino , Camundongos , MicroRNAs/genética , NF-kappa B/genética , Transdução de Sinais/genética , Proteínas Smad/genética , Fator de Crescimento Transformador beta1/genéticaRESUMO
Exposure to reactive oxygen species can easily result in serious diseases, such as hyperproliferative skin disorders or skin cancer. Herbal extracts are widely used as antioxidant sources in different compositions. The importance of antioxidant therapy in inflammatory conditions has increased. Innovative formulations can be used to improve the effects of these phytopharmacons. The bioactive compounds of Plantago lanceolata (PL) possess different effects, such as anti-inflammatory, antioxidant, and bactericidal pharmacological effects. The objective of this study was to formulate novel liquid crystal (LC) compositions to protect Plantago lanceolata extract from hydrolysis and to improve its effect. Since safety is an important aspect of pharmaceutical formulations, the biological properties of applied excipients and blends were evaluated using assorted in vitro methods on HaCaT cells. According to the antecedent toxicity screening evaluation, three surfactants were selected (Gelucire 44/14, Labrasol, and Lauroglycol 90) for the formulation. The dissolution rate of PL from the PL-LC systems was evaluated using a Franz diffusion chamber apparatus. The antioxidant properties of the PL-LC systems were evaluated with 2,2-diphenyl-1-picrylhydrazyl (DPPH) and malondialdehyde (MDA) assessments. Our results suggest that these compositions use a nontraditional, rapid-permeation pathway for the delivery of drugs, as the applied penetration enhancers reversibly alter the barrier properties of the outer stratum corneum. These excipients can be safe and highly tolerable thus, they could improve the patient's experience and promote adherence.
Assuntos
Composição de Medicamentos , Cristais Líquidos/química , Extratos Vegetais/farmacologia , Plantago/química , Pele/efeitos dos fármacos , Compostos de Bifenilo/química , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Impedância Elétrica , Sequestradores de Radicais Livres/farmacologia , Células HaCaT , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos da radiação , Malondialdeído/metabolismo , Permeabilidade , Picratos/química , Pele/efeitos da radiação , Raios UltravioletaRESUMO
Several drugs have poor oral bioavailability due to low or incomplete absorption which is affected by various effects as pH, motility of GI, and enzyme activity. The gastroretentive drug delivery systems are able to deal with these problems by prolonging the gastric residence time, while increasing the therapeutic efficacy of drugs. Previously, we developed a novel technology to foam hot and molten dispersions on atmospheric pressure by a batch-type in-house apparatus. Our aim was to upgrade this technology by a new continuous lab-scale apparatus and confirm that our formulations are gastroretentive. At first, we designed and built the apparatus and continuous production was optimized using a Box-Behnken experimental design. Then, we formulated barium sulfate-loaded samples with the optimal production parameters, which was suitable for in vivo imaging analysis. In vitro study proved the low density, namely 507 mg/cm3, and the microCT record showed high porosity with 40 µm average size of bubbles in the molten suspension. The BaSO4-loaded samples showed hard structure at room temperature and during the wetting test, the complete wetting was detected after 120 min. During the in vivo study, the X-ray taken showed the retention of the formulation in the rat stomach after 2 h. We can conclude that with our device low-density floating formulations were prepared with prolonged gastric residence time. This study provides a promising platform for marketed active ingredients with low bioavailability.
Assuntos
Sulfato de Bário/síntese química , Sulfato de Bário/farmacocinética , Sistemas de Liberação de Medicamentos/métodos , Absorção Gastrointestinal/efeitos dos fármacos , Animais , Sulfato de Bário/administração & dosagem , Disponibilidade Biológica , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/síntese química , Preparações de Ação Retardada/farmacocinética , Formas de Dosagem , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/metabolismo , Absorção Gastrointestinal/fisiologia , Masculino , Porosidade , Ratos , Ratos Endogâmicos F344RESUMO
Natural products used in the treatment of acne vulgaris may be promising alternative therapies with fewer side effects and without antibiotic resistance. The objective of this study was to formulate creams containing Spirulina (Arthrospira) platensis to be used in acne therapy. Spirulina platensis belongs to the group of micro algae and contains valuable active ingredients. The aim was to select the appropriate nonionic surfactants for the formulations in order to enhance the diffusion of the active substance and to certify the antioxidant and antibacterial activity of Spirulina platensis-containing creams. Lyophilized Spirulina platensis powder (SPP) was dissolved in Transcutol HP (TC) and different types of nonionic surfactants (Polysorbate 60 (P60), Cremophor A6:A25 (CR) (1:1), Tefose 63 (TFS), or sucrose ester SP 70 (SP70)) were incorporated in creams as emulsifying agents. The drug release was evaluated by the Franz diffusion method and biocompatibility was tested on HaCaT cells. In vitro antioxidant assays were also performed, and superoxide dismutase (SOD) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays were executed. Antimicrobial activities of the selected compositions were checked against Staphylococcus aureus (S. aureus) and Cutibacteriumacnes (C. acnes) (formerly Propionibacterium acnes) with the broth microdilution method. Formulations containing SP 70 surfactant with TC showed the most favorable dissolution profiles and were found to be nontoxic. This composition also showed significant increase in free radical scavenger activity compared to the blank sample and the highest SOD enzyme activity was also detected after treatment with the cream samples. In antibacterial studies, significant differences were observed between the treated and control groups after an incubation time of 6 h.
Assuntos
Acne Vulgar/tratamento farmacológico , Antibacterianos/farmacologia , Materiais Biocompatíveis/farmacologia , Produtos Biológicos/farmacologia , Spirulina/química , Tensoativos/farmacologia , Acne Vulgar/microbiologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Materiais Biocompatíveis/química , Materiais Biocompatíveis/isolamento & purificação , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Composição de Medicamentos , Humanos , Testes de Sensibilidade Microbiana , Pós , Propionibacteriaceae/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Tensoativos/química , Tensoativos/isolamento & purificaçãoRESUMO
One of the most promising emerging innovations in personalized medication is based on 3D printing technology. For use as authorized medications, 3D-printed products require different in vitro tests, including dissolution and biocompatibility investigations. Our objective was to manufacture implantable drug delivery systems using fused deposition modeling, and in vitro tests were performed for the assessment of these products. Polylactic acid, antibacterial polylactic acid, polyethylene terephthalate glycol, and poly(methyl methacrylate) filaments were selected, and samples with 16, 19, or 22 mm diameters and 0%, 5%, 10%, or 15% infill percentages were produced. The dissolution test was performed by a USP dissolution apparatus 1. A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide dye (MTT)-based prolonged cytotoxicity test was performed on Caco-2 cells to certify the cytocompatibility properties. The implantable drug delivery systems were characterized by thermogravimetric and heatflow assay, contact angle measurement, scanning electron microscopy, microcomputed tomography, and Raman spectroscopy. Based on our results, it can be stated that the samples are considered nontoxic. The dissolution profiles are influenced by the material properties of the polymers, the diameter, and the infill percentage. Our results confirm the potential of fused deposition modeling (FDM) 3D printing for the manufacturing of different implantable drug delivery systems in personalized medicine and may be applied during surgical interventions.
Assuntos
Anti-Inflamatórios não Esteroides , Diclofenaco , Impressão Tridimensional , Próteses e Implantes , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/química , Tecnologia Biomédica , Fenômenos Químicos , Diclofenaco/administração & dosagem , Diclofenaco/química , Fenômenos Mecânicos , Polímeros/química , Solubilidade , Termogravimetria , Microtomografia por Raio-XRESUMO
Dosage forms with increased gastric residence time are promising tools to increase bioavailability of drugs with narrow absorption window. Low-density floating formulations could avoid gastric emptying; therefore, sustained drug release can be achieved. Our aim was to develop a new technology to produce low-density floating formulations by melt foaming. Excipients were selected carefully, with the criteria of low gastric irritation, melting range below 70°C and well-known use in oral drug formulations. PEG 4000, Labrasol and stearic acid type 50 were used to create metronidazole dispersion which was foamed by air on atmospheric pressure using in-house developed apparatus at 53°C. Stearic acid was necessary to improve the foamability of the molten dispersion. Additionally, it reduced matrix erosion, thus prolonging drug dissolution and preserving hardness of the moulded foam. Labrasol as a liquid solubiliser can be used to increase drug release rate and drug solubility. Based on the SEM images, metronidazole in the molten foam remained in crystalline form. MicroCT scans with the electron microscopic images revealed that the foam has a closed-cell structure, where spherical voids have smooth inner wall, they are randomly dispersed, while adjacent voids often interconnected with each other. Drug release from all compositions followed Korsmeyer-Peppas kinetic model. Erosion of the matrix was the main mechanism of the release of metronidazole. Texture analysis confirmed that stearic acid plays a key role in preserving the integrity of the matrix during dissolution in acidic buffer. The technology creates low density and solid matrix system with micronsized air-filled voids.
Assuntos
Formas de Dosagem , Temperatura Alta , Metronidazol/química , Estômago , Disponibilidade Biológica , Preparações de Ação Retardada , Composição de Medicamentos , Liberação Controlada de Fármacos , Excipientes/química , Esvaziamento Gástrico , Metronidazol/farmacocinética , Solubilidade , Ácidos Esteáricos/químicaRESUMO
In this current article matrix formulations for oral drug delivery are reviewed. Conventional dosage forms and novel applications such as 3D printed matrices and aerogel matrices are discussed. Beside characterization, excipients and matrix forming agents are also enlisted and classified. The incorporated drug could exist in crystalline or in amorphous forms, which makes drug dissolution easily tunable. Main drug release mechanisms are detailed and reviewed to support rational design in pharmaceutical technology and manufacturing considering the fact that R&D members of the industry are forced to obtain knowledge about excipients and methods pros and cons. As innovative and promising research fields of drug delivery, 3D printed products and highly porous, low density aerogels with high specific surface area are spreading, currently limitlessly. These compositions can also be considered as matrix formulations.
Assuntos
Formas de Dosagem , Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Preparações Farmacêuticas/administração & dosagem , Administração Oral , Preparações Farmacêuticas/química , PorosidadeRESUMO
Self-emulsifying drug delivery systems (SEDDS) are regarded as a potential implement for oral delivery of water insoluble APIs to overcome their poor and irregular bioavailability. The correlation between the physicochemical parameters and the behavior of self-emulsifying drug delivery systems was established. The objective of this study was to summarize these physicochemical factors characterized SEDDS. Determination of self-emulsification process and ternary phase diagram are the basis of preparations. The position of APIs in SEDDS inclusion can be determined by dye solubilisation test. The end point of self-emulsification was controlled by turbimetric evaluation. Optimisation of droplet size and zeta potential are crucial parameters because they can influence i.e. the dissolution rate of APIs and the stability of SEDDS. Besides the basic methods in the characterization of SEDDS such as dispersibility tests, turbidimetric evaluation, viscosity tests, determinations with complex instruments such as photon correlation spectroscopy or dynamic light-scattering, electro kinetic potential measurement, non-destructive spectroscopic techniques (LFDS, FTIR, RS) and various microscopic techniques (SEM, PLM, EDS) has also been described.
Assuntos
Sistemas de Liberação de Medicamentos , Emulsões , Microscopia/métodos , Nefelometria e Turbidimetria , Preparações Farmacêuticas/administração & dosagem , Preparações Farmacêuticas/química , Solubilidade , Análise Espectral/métodos , ViscosidadeRESUMO
Nowadays, the safety of parabens as pharmaceutical preservatives is debated. Recent studies investigated their interference with the oestrogen receptors, nevertheless their carcinogenic activity was also proved. That was the reason why the re-evaluation of the biocompatibility and antimicrobial activity of parabens is required using modern investigation methods. We aimed to test the cytotoxic, antifungal and antibacterial effect of parabens on Caco-2 cells, C. albicans, C. parapsilosis, C. glabrata, E. coli, P. aeruginosa and S. aureus. Two complex systems (glycerol-Polysorbate 20; ethanol-Capryol PGMC™) were formulated to study-with the MTT-assay and microdilution method, respectively-how other excipients may modify the biocompatibility and antimicrobial effect of parabens. In the case of cytotoxicity, the toxicity of these two systems was highly influenced by co-solvents and surfactants. The fungi and bacteria had significantly different resistance in the formulations and in some cases the excipients could highly modify the effectiveness of parabens both in an agonistic and in a counteractive way. These results indicate that with appropriate selection, non-preservative excipients can contribute to the antimicrobial safety of the products, thus they may decrease the required preservative concentration.
Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Excipientes/química , Anti-Infecciosos/administração & dosagem , Bactérias/efeitos dos fármacos , Células CACO-2 , Sobrevivência Celular/efeitos dos fármacos , Composição de Medicamentos , Fungos/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Estrutura Molecular , Soluções , SolventesRESUMO
A new technology was developed to form extended release hard gelatin capsules, based on the lipid matrix formation of Gelucire 50/13 and cetostearyl alcohol. Matrices were formed in situ by filling pulverised lipids, ethylcellulose and active ingredients such as diclofenac sodium, acetaminophen and metronidazol into capsules and heating at 63°C for 11 min. Effects of heating were investigated also on the brittleness of capsule shells. Inhibition of the evaporation of water reduced capsule damage. Dissolution tests and texture analysis were performed to discover the release and mechanical profiles of the matrices. Tests were repeated after 1 month storage and results were compared. Gelucire 50/13 alone prolonged drug release but cetostearyl alcohol slowed drug liberation even further. Drug release from all compositions was found to follow first-order kinetic. Significant softening of the matrices was detected during storage in composition containing only Gelucire 50/13, ethylcellulose and diclofenac sodium. Thermal analysis and IR tests were also performed to discover physicochemical interactions between active pharmaceutical ingredients and excipients. Thermal analysis confirmed a notable interaction between diclofenac sodium and Gelucire 50/13 which could be the cause of the observed softening. In conclusion, modified release hard gelatin capsules were developed by a simple and fast monolithic lipid matrix formation method.
Assuntos
Cápsulas/química , Gelatina/química , Lipídeos/química , Tecnologia Farmacêutica , Diclofenaco/química , Composição de Medicamentos , Liberação Controlada de Fármacos , Gorduras/química , Óleos/química , SolubilidadeRESUMO
The most important components of Plantago lanceolata L. leaves are catalpol, aucubin, and acteoside (=verbascoside). These bioactive compounds possess different pharmacological effects: anti-inflammatory, antioxidant, antineoplastic, and hepatoprotective. The aim of this study was to protect Plantago lanceolata extract from hydrolysis and to improve its antioxidant effect using self-nano-emulsifying drug delivery systems (SNEDDS). Eight SNEDDS compositions were prepared, and their physical properties, in vitro cytotoxicity, and in vivo AST/ALT values were investigated. MTT cell viability assay was performed on Caco-2 cells. The well-diluted samples (200 to 1000-fold dilutions) proved to be non-cytotoxic. The acute administration of PL-SNEDDS compositions resulted in minor changes in hepatic markers (AST, ALT), except for compositions 4 and 8 due to their high Transcutol contents (80%). The non-toxic compositions showed a significant increase in free radical scavenger activity measured by the DPPH test compared to the blank SNEDDS. An indirect dissolution test was performed, based on the result of the DPPH antioxidant assay; the dissolution profiles of Plantago lancolata extract were statistically different from each SNEDDS. The anti-inflammatory effect of PL-SNEDDS compositions was confirmed by the ear inflammation test. For the complete examination period, all compositions decreased ear edema as compared to the positive (untreated) control. It can be concluded that PL-SNEDDS compositions could be used to deliver active natural compounds in a stable, efficient, and safe manner.