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2.
Toxicol In Vitro ; 69: 104995, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32891721

RESUMEN

The ISO 10993 standards on biocompatibility assessment of medical devices discourage the use of animal tests when reliable and validated in vitro methods are available. A round robin validation study of in vitro reconstructed human epidermis (RhE) assays was performed as potential replacements for rabbit skin irritation testing. The RhE assays were able to accurately identify strong irritants in dilute medical device extracts. However, there was some uncertainty about whether RhE tissues accurately predicted the results of the rabbit skin patch or intracutaneous irritation test. To address that question, this paper presents in vivo data from the round robin and subsequent follow-up studies. The follow-up studies included simultaneous in vitro RhE model and in vivo testing of round robin polymer samples and the results of dual in vitro/in vivo testing of currently marketed medical device components/materials. Our results show for the first time that for both pure chemicals and medical device extracts the intracutaneous rabbit test is more sensitive to detect irritant activity than the rabbit skin patch test. The studies showed that the RhE models produced results that were essentially equivalent to those from the intracutaneous rabbit skin irritation test. Therefore, it is concluded that RhE in vitro models are acceptable replacements for the in vivo rabbit intracutaneous irritation test for evaluating the irritant potential of medical devices.


Asunto(s)
Alternativas a las Pruebas en Animales , Epidermis/efectos de los fármacos , Equipos y Suministros/efectos adversos , Irritantes/toxicidad , Pruebas de Irritación de la Piel/métodos , Administración Tópica , Animales , Femenino , Ácidos Heptanoicos/toxicidad , Humanos , Técnicas In Vitro , Inyecciones Intradérmicas , Ácido Láctico/toxicidad , Masculino , Conejos , Reproducibilidad de los Resultados
3.
Biomed Res Int ; 2020: 3419034, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32685468

RESUMEN

Two enantiomers of lactic acid exist. While L-lactic acid is a common compound of human metabolism, D-lactic acid is produced by some strains of microorganism or by some less relevant metabolic pathways. While L-lactic acid is an endogenous compound, D-lactic acid is a harmful enantiomer. Exposure to D-lactic acid can happen by various ways including contaminated food and beverages and by microbiota during some pathological states like short bowel syndrome. The exposure to D-lactic acid cannot be diagnosed because the common analytical methods are not suitable for distinguishing between the two enantiomers. In this review, pathways for D-lactic acid, pathological processes, and diagnostical and analytical methods are introduced followed by figures and tables. The current literature is summarized and discussed.


Asunto(s)
Ácido Láctico/metabolismo , Ácido Láctico/toxicidad , Metaboloma , Acidosis/sangre , Acidosis/diagnóstico , Acidosis/terapia , Animales , Humanos , Ácido Láctico/sangre , Ácido Láctico/química , Redes y Vías Metabólicas
4.
Drug Deliv Transl Res ; 9(3): 694-706, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30825078

RESUMEN

Diabetes mellitus is a chronic metabolic disorder characterized by insulin deficiency and impaired glucose metabolism. Overexpression of cAMP response element binding protein (CREB)-regulated transcriptional coactivator 2 (CRTC2) plays an important role in high gluconeogenesis in patients with diabetes type II. Using RNA interference technology for silencing CRTC2 gene expression could be helpful in controlling the level of blood glucose and gluconeogenesis. In this study, we designed a siRNA delivery platform comprising blended chitosan lactate (CT) and polyethylene glycol (PEG) conjugated with glycyrrhetinic acid (GA) for controlling gluconeogenesis. The nanoparticles showed spherical and smooth surface with ~ 189-nm size and + 5.1 zeta potential. Targeted nanoparticles were efficiently stable in serum and different levels of heparin media over 48 h. The gene knockdown efficiency of nanoparticles was comparable to Lipofectamine®, while they had no significant in vitro and in vivo toxicity. The in vivo therapeutic efficacy of targeted nanoparticles was also confirmed by reduced amount of fasting blood sugar in diabetic rat models. Furthermore, the nanoparticles were mostly accumulated in the liver after 2 h indicating the significant targeting ability of the prepared nanoparticles. Therefore, CT/PEG-GA nanoparticles can be considered as a potential candidate for targeted delivery of siRNA into hepatocytes in order to regulate gluconeogenesis in diabetes.


Asunto(s)
Quitosano/administración & dosificación , Gluconeogénesis/efectos de los fármacos , Ácido Glicirretínico/administración & dosificación , Ácido Láctico/administración & dosificación , Hígado/efectos de los fármacos , Nanopartículas/administración & dosificación , Polietilenglicoles/administración & dosificación , ARN Interferente Pequeño/administración & dosificación , Factores de Transcripción/genética , Animales , Quitosano/farmacocinética , Quitosano/toxicidad , Diabetes Mellitus Experimental/sangre , Diabetes Mellitus Experimental/terapia , Expresión Génica , Ácido Glicirretínico/farmacocinética , Ácido Glicirretínico/toxicidad , Células Hep G2 , Humanos , Ácido Láctico/farmacocinética , Ácido Láctico/toxicidad , Hígado/metabolismo , Hígado/patología , Masculino , Nanopartículas/toxicidad , Polietilenglicoles/farmacocinética , Polietilenglicoles/toxicidad , ARN Interferente Pequeño/farmacocinética , ARN Interferente Pequeño/toxicidad , Ratas Wistar , Distribución Tisular
5.
Toxicol In Vitro ; 57: 164-173, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30851411

RESUMEN

The incidence of sensitive skin with stinging and itch following chemical exposure in products such as cosmetics is increasing, but molecular mechanisms underlying this pathophysiology remain understudied. Here we performed transcriptional analysis of reconstructed human epidermis (RHE) 1, 6, and 24 h following topical lactic acid (LA) application, a known inducer of the sensitive skin reaction. Since little is known about the specific role of keratinocyte transcriptional changes in mediating stinging and itch, we performed pathway analysis using several publically available databases and then focused on significantly changed transcripts involved in stress responses and itch signaling using the Comparative Toxicogenomics Database. LA treatment induced damage-associated genes HSPA1A, DDIT3, IL1A, and HMGB2. Neurotrophic factors including BDNF, ARTN, PGE2, and chemokines were also upregulated. Stimulation of the RHE with 5% LA did not reduce cell viability, but reduced the trans-epidermal electric resistance, suggesting barrier dysfunction. Accordingly, skin barrier formation genes such as filaggrins (FLG, FLG2) and corneodesmosin (CDSN) were downregulated. To our knowledge, this is the first study focusing on transcriptional changes underlying the stinging response of keratinocytes upon LA stimulation. While follow-up research is needed, this study provides new insight into the mechanisms underlying the sensitive skin reaction.


Asunto(s)
Epidermis/efectos de los fármacos , Irritantes/toxicidad , Ácido Láctico/toxicidad , Prurito/genética , Transcriptoma/efectos de los fármacos , Epidermis/metabolismo , Proteínas Filagrina , Humanos
6.
Glia ; 67(1): 27-36, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30430652

RESUMEN

Astrocytes play a key role in the maintenance of synaptic transmission by producing L-lactate via the astrocyte-neuron lactate shuttle (ANLS). Astrocyte activation in the spinal cord is involved in the expression of neuropathic pain. We investigated the role of the ANLS in the spinal cord on hyperalgesia in neuropathic pain in mice. Specific activation of dorsal horn astrocytes induced mechanical hyperalgesia, which was attenuated by α-cyano-4-hydroxycinnamate (4-CIN), an inhibitor of monocarboxylate transporters that deliver L-lactate from astrocytes to neurons. Intrathecal L-lactate administration lowered the mechanical nociceptive threshold, which was attenuated by pretreatment with 4-CIN and isosafrole (a lactate dehydrogenase inhibitor), but not gliotoxin. Intrathecal L-lactate administration significantly upregulated c-Fos and cofilin phosphorylation, which was reversed by 4-CIN. The lowered mechanical nociceptive threshold was significantly attenuated by intrathecal fluorocitrate (an astrocyte-specific Krebs cycle inhibitor), 4-CIN, and isosafrole treatment. Thus, these results suggested that, in neuropathic pain, mechanical hyperalgesia was maintained by excessive L-lactate supplied by activated astrocytes via an aberrant ANLS.


Asunto(s)
Astrocitos/metabolismo , Hiperalgesia/metabolismo , Ácido Láctico/metabolismo , Neuronas/metabolismo , Nocicepción/fisiología , Médula Espinal/metabolismo , Animales , Astrocitos/efectos de los fármacos , Hiperalgesia/inducido químicamente , Inyecciones Espinales , Ácido Láctico/administración & dosificación , Ácido Láctico/toxicidad , Masculino , Ratones , Neuronas/efectos de los fármacos , Nocicepción/efectos de los fármacos , Médula Espinal/efectos de los fármacos
7.
J Agric Food Chem ; 66(30): 7889-7898, 2018 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-30039704

RESUMEN

The use of herbicides plays a vital role in controlling weeds and conserving crops; however, its usage generates both environmental and economic problems. For example, herbicides pose a financial issue as farmers must apply large quantities to protect crops due to absorption rates of less than 0.1%. Therefore, there is a great need for the development of new methods to mitigate these issues. Here, we report for the first time the synthesis of poly(lactic- co-glycolic-acid) (PLGA) nanoherbicides loaded with atrazine as an active ingredient. We used potato plants as a biological model to assess the herbicidal activity of the engineered PLGA nanoherbicides. Our method produced nanoherbicides with an average size of 110 ± 10 nm prior to lyophilization. Fifty percent of the loaded atrazine in the PLGA matrix is released in 72 h. Furthermore, we performed Monte Carlo simulations to determine the chemical interaction among atrazine, PLGA, and the solvent system. One of the most significant outcomes of these simulations was to find the formation of a hydrogen bond of 1.9 Å between PLGA and atrazine, which makes this interaction very stable. Our in vitro findings showed that as atrazine concentration is increased in PLGA nanoparticles, potato plants undergo a significant decrease in stem length, root length, fresh weight, dry weight, and the number of leaves, with root length being the most affected. These experimental results suggest the herbicidal effectiveness of atrazine-loaded PLGA nanoherbicides in inhibiting the growth of the potato plant. Hence, we present the proof-of-concept for using PLGA nanoherbicides as an alternative method for inhibiting weed growth. Future studies will involve a deep understanding of the mechanism of plant-nanoherbicide interaction as well as the role of PLGA as a growth potentiator.


Asunto(s)
Atrazina/química , Portadores de Fármacos/química , Herbicidas/química , Ácido Láctico/química , Nanopartículas/química , Ácido Poliglicólico/química , Portadores de Fármacos/toxicidad , Composición de Medicamentos , Herbicidas/toxicidad , Ácido Láctico/toxicidad , Nanopartículas/toxicidad , Tamaño de la Partícula , Ácido Poliglicólico/toxicidad , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Solanum tuberosum/efectos de los fármacos , Solanum tuberosum/crecimiento & desarrollo
8.
Int J Pharm ; 545(1-2): 318-328, 2018 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-29746999

RESUMEN

Plasmid DNA (pDNA) vaccines have the potential for protection against a wide range of diseases including rabies but are rapid in degradation and poor in uptake by antigen-presenting cells. To overcome the limitations, we fabricated a pDNA nanoparticulate vaccine. The negatively charged pDNA was adsorbed onto the surface of cationic PLGA (poly (d, l-lactide-co-glycolide))-chitosan nanoparticles and were used as a delivery vehicle. To create a hydrogel for sustainable vaccine release, we dispersed the pDNA nanoparticles in poloxamer 407 gel which is liquid at 4 °C and turns into soft gels at 37 °C, providing ease of administration and preventing burst release of pDNA. Complete immobilization of pDNA to cationic nanoparticles was achieved at a pDNA to nanoparticles ratio (P/N) of 1/50. Cellular uptake of nanoparticles was both time and concentration dependent and followed a saturation kinetics with Vmax of 11.389 µg/mL h and Km of 139.48 µg/mL. The in vitro release studies showed the nanoparticulate vaccine has a sustained release for up to 24 days. In summary, pDNA PLGA-chitosan nanoparticles were non-cytotoxic, their buffering capacity and cell uptake were enhanced, and sustained the release of pDNA. We expect our pDNA vaccine's potency will be greatly improved in the animal studies.


Asunto(s)
Quitosano/química , Portadores de Fármacos , Ácido Láctico/química , Nanopartículas , Poloxámero/química , Ácido Poliglicólico/química , Vacunas Antirrábicas/química , Animales , Línea Celular , Quitosano/toxicidad , Células Dendríticas/efectos de los fármacos , Células Dendríticas/inmunología , Composición de Medicamentos , Liberación de Fármacos , Estabilidad de Medicamentos , Ensayo de Cambio de Movilidad Electroforética , Hidrogeles , Cinética , Ácido Láctico/toxicidad , Ratones Endogámicos C57BL , Nanotecnología , Poloxámero/toxicidad , Ácido Poliglicólico/toxicidad , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Vacunas Antirrábicas/administración & dosificación , Vacunas Antirrábicas/inmunología , Vacunas Antirrábicas/metabolismo , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de Superficie , Tecnología Farmacéutica/métodos , Vacunas de ADN/química , Vacunas de ADN/inmunología
9.
Arch Dermatol Res ; 310(6): 495-504, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29728858

RESUMEN

We determined whether compensating ceramides in the stratum corneum (SC) may ameliorate the impaired barrier function and subsequently attenuate the enhanced skin sensitivity. Treatment for 4 weeks with the ceramide complex cream or the placebo cream significantly ameliorated the intensity of lactic acid sensations in 39 female subjects with sensitive skin, the degree of which was attenuated to a greater extent at 1 week by the ceramide complex cream compared with the placebo cream. The amelioration of skin sensations was accompanied by a significant increase in total ceramide content in the SC elicited by the ceramide complex cream that was significantly more effective than the placebo cream at 4 weeks. Consistently, TEWL and conductance values were significantly decreased or increased at 1 and 4 weeks, respectively, to a greater extent by the ceramide complex cream than by the placebo cream. TEWL levels were significantly correlated with the increased levels of SC total ceramide in the ceramide complex cream-treated skin but not in the placebo cream-treated skin. Thus, the amelioration of lactic acid sensations by topical application of a ceramide complex cream, provides a deep insight into the pathophysiology of sensitive skin as a reduced barrier function-dependent sub-clinical sensory response.


Asunto(s)
Ceramidas/farmacología , Epidermis/efectos de los fármacos , Extractos Vegetales/farmacología , Fenómenos Fisiológicos de la Piel/efectos de los fármacos , Administración Cutánea , Ceramidas/biosíntesis , Método Doble Ciego , Quimioterapia Combinada/métodos , Epidermis/inervación , Epidermis/metabolismo , Eucalyptus/química , Femenino , Voluntarios Sanos , Humanos , Ácido Láctico/toxicidad , Placebos , Sensación/efectos de los fármacos , Crema para la Piel , Pérdida Insensible de Agua/efectos de los fármacos
10.
Toxicol In Vitro ; 50: 433-438, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29462660

RESUMEN

Several irritants were used in the in vitro irritation medical device round robin. The objective of this study was to verify their irritation potential using the human patch test (HPT), an in vitro assay, and in vivo data. The irritants were lactic acid (LA), heptanoic acid (HA), sodium dodecyl sulfate (SDS), Genapol® X-80 (GP), and Y-4 polymer. Dilute saline and sesame seed oil (SSO) solutions of each were evaluated using a 4 and 18 h HPT and the EpiDerm™ SIT-MD RhE assay; results were then compared to existing rabbit skin irritation test data. Results from the 4 h HPT were negative in most cases except for GP and SDS, while the 18 h HPT also identified some LA, HA, and GP samples as irritants. EpiDerm™ SIT-MD correctly identified all irritants except GP in SSO due to limited solubility. Data from cutaneous rabbit irritation tests were negative, while all intracutaneous results were strongly or weakly positive except for the most dilute GP solutions. These findings indicate that EpiDerm™ SIT-MD results correlate with those from the rabbit intracutaneous test and confirm that RhE assays are suitable replacements for animals in evaluating the tissue irritation potential of medical devices.


Asunto(s)
Equipos y Suministros , Irritantes/toxicidad , Pruebas del Parche/métodos , Pruebas de Irritación de la Piel/métodos , Alternativas a las Pruebas en Animales , Animales , Benchmarking , Ácidos Heptanoicos/toxicidad , Humanos , Ácido Láctico/toxicidad , Polietilenglicoles/toxicidad , Cloruro de Polivinilo/toxicidad , Conejos , Reproducibilidad de los Resultados , Piel/efectos de los fármacos , Dodecil Sulfato de Sodio/toxicidad
11.
J Cell Physiol ; 233(2): 1168-1178, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28464242

RESUMEN

Magnetic nanoparticles (MNPs) are used as contrast agents and targeted drug delivery systems (TDDS) due to their favorable size, surface charge, and magnetic properties. Unfortunately, the toxicity associated with MNPs limits their biological applications. Surface functionalization of MNPs with selective polymers alters the surface chemistry to impart better biocompatibility. We report the preparation of surface functionalized MNPs using iron oxide NPs (MNPs), poly (lactic-co-glycolic acid) (PLGA), and sodium alginate via co-precipitation, emulsification, and electro-spraying, respectively. The NPs are in the nanosize range and negatively charged. Morphological and structural analyses affirm the surface functionalized nanostructure of the NPs. The surface functionalized MNPs are biocompatible, and demonstrate enhanced intracellular delivery under an applied magnetic field (H), which evinces the targeting ability of MNPs. After NP treatment, the physico-mechanical properties of fibroblasts are decided by the selective MNP uptake under "on" or "off" magnetic field conditions. We envision potential use of biocompatible surface functionalized MNP for intracellular-, targeted-DDS, imaging, and for investigating cellular mechanics.


Asunto(s)
Alginatos/química , Materiales Biocompatibles/química , Reactivos de Enlaces Cruzados/química , Ácido Láctico/química , Campos Magnéticos , Magnetismo/métodos , Nanopartículas de Magnetita/química , Nanomedicina/métodos , Ácido Poliglicólico/química , Alginatos/metabolismo , Alginatos/toxicidad , Animales , Materiales Biocompatibles/metabolismo , Materiales Biocompatibles/toxicidad , Transporte Biológico , Supervivencia Celular/efectos de los fármacos , Reactivos de Enlaces Cruzados/metabolismo , Reactivos de Enlaces Cruzados/toxicidad , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Fibroblastos/patología , Ácido Glucurónico/química , Ácido Glucurónico/metabolismo , Ácido Glucurónico/toxicidad , Ácidos Hexurónicos/química , Ácidos Hexurónicos/metabolismo , Ácidos Hexurónicos/toxicidad , Ácido Láctico/metabolismo , Ácido Láctico/toxicidad , Nanopartículas de Magnetita/toxicidad , Ratones , Células 3T3 NIH , Tamaño de la Partícula , Ácido Poliglicólico/metabolismo , Ácido Poliglicólico/toxicidad , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Propiedades de Superficie
12.
J Dermatol Sci ; 89(1): 33-39, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29122406

RESUMEN

BACKGROUND: Sensitive skin is a condition of cutaneous hypersensitivity to environmental factors. Lactic acid stinging test (LAST) is commonly used to assess sensitive skin and composed of four distinct sensations (pain, burning sensation, itch, and crawly feeling). A link between sensitive skin and barrier dysfunction has been proposed in atopic dermatitis (AD) patients. However, clinical and laboratory factors that are associated with sensitive skin remain unelucidated. OBJECTIVE: To investigate relationship between sensitive skin and AD-associated markers. METHODS: Forty-two Japanese AD patients and 10 healthy subjects (HS) were enrolled. AD patients were divided into extrinsic (EAD; high IgE levels) and intrinsic (IAD; normal IgE levels) types. We conducted 1% LAST by assessing the four distinct sensations and calculated the frequencies of sensitive skin in EAD, IAD, and HS. We also performed clinical AD-related tests, including transepidermal water loss (TEWL), visual analogue scale (VAS) of pruritus, and quality of life, and measured laboratory markers, including blood levels of IgE, CCL17/TARC, lactate dehydrogenase (LDH) and eosinophil counts, and concentration levels of serum Th1/Th2 cytokines. Filaggrin (FLG) mutations were examined in 21 patients. These values were subjected to correlation analyses with each of the four sensation elements. RESULTS: According to the standard criteria for LAST positivity, the frequencies of LAST-positive subjects were 54.8% and 10.0% in AD and HS, respectively (P=0.014). EAD patients showed a significantly (P=0.026) higher frequency of positive LAST (65.6%) than did IAD patients (20.0%). Among the four LAST sensation elements, the crawly feeling and pain scores positively correlated with VAS of pruritus, total serum IgE, mite-specific IgE, CCL17/TARC, and/or LDH. There was no association of the LAST scores with serum Th1/Th2 cytokine levels. Notably, neither TEWL nor FLG mutations correlated with LAST positivity or any sensation scores. CONCLUSIONS: The frequency of sensitive skin is higher in EAD than in IAD. Sensitive skin is associated with AD severity, but not necessarily with barrier condition.


Asunto(s)
Dermatitis Atópica/inmunología , Piel/inmunología , Pérdida Insensible de Agua/fisiología , Adulto , Anciano , Biomarcadores/sangre , Citocinas/sangre , Dermatitis Atópica/sangre , Dermatitis Atópica/genética , Dermatitis Atópica/patología , Femenino , Proteínas Filagrina , Humanos , Inmunoglobulina E/sangre , Proteínas de Filamentos Intermediarios/genética , Ácido Láctico/toxicidad , Masculino , Persona de Mediana Edad , Prurito/sangre , Prurito/genética , Prurito/inmunología , Prurito/patología , Índice de Severidad de la Enfermedad , Piel/fisiopatología , Pruebas de Irritación de la Piel/métodos
13.
Pharm Dev Technol ; 23(4): 324-333, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27670289

RESUMEN

Frequent intravitreal injections are currently used to overcome the ocular barriers and provide sufficient drug to the posterior eye segment. However, intravitreal injections have been associated with a number of complications and high treatment costs. To overcome these limitations, peptide-loaded poly(d,l-lactic-co-glycolic acid) nanoparticles (PLGA NPs) were developed using the nanoprecipitation technique and were optimized via Box-Behnken Design (BBD) and Response Surface Methodology (RSM). Developed NPs were evaluated for potential toxicity and cell apoptosis using the zebrafish embryo toxicity (ZET) model with titanium dioxide NPs and ethanol (1% v/v) serving as positive controls. Developed NPs had a size of 75.6-153.8 nm, a polydispersity index between 0.11 and 0.25 and a zeta potential of -9.4 to -46.0 mV. Loaded peptide was found to be stable under various experimental conditions tested. BBD and RSM were validated through the characterization of optimized formulations. Survival and hatching rates of NP-treated zebrafish 0-144 h post-fertilization were found to be normal with no significant malformations. Cellular apoptosis studies also endorsed the non-cytotoxic nature of the NPs. The overall results indicate that optimized PLGA nanoparticles could be a promising platform for efficient peptide delivery to the posterior segment of the eye.


Asunto(s)
Portadores de Fármacos/toxicidad , Ácido Láctico/toxicidad , Nanopartículas/toxicidad , Péptidos/administración & dosificación , Ácido Poliglicólico/toxicidad , Animales , Apoptosis/efectos de los fármacos , Portadores de Fármacos/administración & dosificación , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos/efectos adversos , Embrión no Mamífero/citología , Embrión no Mamífero/efectos de los fármacos , Embrión no Mamífero/fisiología , Inyecciones Intravítreas , Ácido Láctico/administración & dosificación , Ácido Láctico/química , Nanopartículas/administración & dosificación , Nanopartículas/química , Péptidos/química , Ácido Poliglicólico/administración & dosificación , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Pruebas de Toxicidad , Pez Cebra/embriología
14.
Molecules ; 22(12)2017 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-29186078

RESUMEN

In response to the demand for new implant materials characterized by high biocompatibility and bioresorption, two prototypes of fibrous nanocomposite implants for osseous tissue regeneration made of a newly developed blend of poly(l-lactide-co-glycolide) (PLGA) and syntheticpoly([R,S]-3-hydroxybutyrate), PLGA/PHB, have been developed and fabricated. Afibre-forming copolymer of glycolide and l-lactide (PLGA) was obtained by a unique method of synthesis carried out in blocksusing Zr(AcAc)4 as an initiator. The prototypes of the implants are composed of three layers of PLGA or PLGA/PHB, nonwoven fabrics with a pore structure designed to provide the best conditions for the cell proliferation. The bioactivity of the proposed implants has been imparted by introducing a hydroxyapatite material and IGF1, a growth factor. The developed prototypes of implants have been subjected to a set of in vitro and in vivobiocompatibility tests: in vitro cytotoxic effect, in vitro genotoxicity and systemic toxicity. Rabbitsshowed no signs of negative reactionafter implantation of the experimental implant prototypes.


Asunto(s)
Implantes Absorbibles , Regeneración Ósea , Hidroxibutiratos , Ácido Láctico/química , Ácido Láctico/farmacología , Nanocompuestos , Poliésteres , Ácido Poliglicólico/química , Ácido Poliglicólico/farmacología , Andamios del Tejido , Animales , Biomarcadores , Línea Celular , Supervivencia Celular , Humanos , Hidroxibutiratos/química , Ácido Láctico/toxicidad , Ratones , Nanocompuestos/química , Poliésteres/química , Ácido Poliglicólico/toxicidad , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Porosidad , Prohibitinas , Conejos , Ingeniería de Tejidos
15.
Invest Ophthalmol Vis Sci ; 58(10): 4274-4285, 2017 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-28850638

RESUMEN

Purpose: Poly(lactic-co-glycolic) acid (PLGA) inserts have been successfully developed for the treatment of posterior eye disease as a means of reducing injection frequency of intravitreally administered therapeutics. PLGA microspheres are also of interest for the delivery of intravitreal drugs, since they offer the advantage of being easily injected without surgical procedures or large injectors. Methods: In the current study, the toxicity of PLGA microspheres and rods was investigated in nonhuman primates (NHPs) and rabbits. An in vitro assessment of cytokine responses to PLGA in peripheral blood mononuclear cells (PBMCs) and macrophages was also performed. Results: Intravitreal administration of 3, 10, or 12.5 mg/eye of PLGA microspheres in NHPs resulted in a severe immune response characterized by a foreign body response. Follow-up studies in the rabbit confirmed this finding for PLGA microspheres ranging in size from 20 to 100 µm. In contrast, administration of PLGA rod implants with a similar PLGA mass did not elicit a significant immune response. In vitro assays in PBMCs and macrophages confirmed proinflammatory cytokine release upon treatment with PLGA microspheres but not PLGA rods. Conclusions: These data demonstrate a lack of tolerability of PLGA microspheres upon intravitreal injection, and suggest that the size, shape, and/or surface area of PLGA depots are critical attributes in determining ocular toxicity.


Asunto(s)
Materiales Biocompatibles/toxicidad , Sistemas de Liberación de Medicamentos/efectos adversos , Ácido Láctico/toxicidad , Microesferas , Ácido Poliglicólico/toxicidad , Animales , Materiales Biocompatibles/administración & dosificación , Citocinas/metabolismo , Modelos Animales de Enfermedad , Reacción a Cuerpo Extraño/metabolismo , Reacción a Cuerpo Extraño/patología , Inyecciones Intravítreas , Ácido Láctico/administración & dosificación , Macrófagos/metabolismo , Ácido Poliglicólico/administración & dosificación , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Conejos , Retina/efectos de los fármacos , Retina/patología , Cuerpo Vítreo/efectos de los fármacos , Cuerpo Vítreo/patología
16.
An Acad Bras Cienc ; 89(2): 1073-1084, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28640354

RESUMEN

This study aimed to evaluate the teratogenic and hepatotoxic potential of the usnic acid encapsulated into PLGA-microspheres. In total, 12 female Wistar rats in pregnancy were randomly distributed in the control group (n= 6) that received 1.0 mL of physiological solution and treatment group (n= 6) that received 25 mg/kg of encapsulated usnic acid by oral administration. All females were euthanized at day 20 of pregnancy and their fetuses were removed and analyzed. During the pregnancy was observed a reduction in weight gain. There was no difference in serum transaminases levels analyzed as well as any difference in liver weight in both groups. The histomorphometric analysis of the liver from the treatment group revealed an increase in number of hepatocytes and a decrease in nuclear area of these cells. Moreover, no alteration was observed in cell area of hepatocytes or number of Kupffer cells. The fetuses had an increase in total number of hepatocytes and a reduction in the amount of megakaryocytes. These results show the hepatotoxic potential of usnic acid during pregnancy. However, its toxicity can be minimized by encapsulation in microspheres.


Asunto(s)
Ascomicetos/química , Benzofuranos/toxicidad , Feto/efectos de los fármacos , Ácido Láctico/toxicidad , Líquenes/química , Hígado/efectos de los fármacos , Ácido Poliglicólico/toxicidad , Anomalías Inducidas por Medicamentos , Animales , Benzofuranos/química , Femenino , Peso Fetal/efectos de los fármacos , Hepatocitos/efectos de los fármacos , Ácido Láctico/química , Hígado/patología , Exposición Materna , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Embarazo , Distribución Aleatoria , Ratas Wistar , Valores de Referencia
17.
An. acad. bras. ciênc ; 89(2): 1073-1084, Apr.-June 2017. tab, graf
Artículo en Inglés | LILACS | ID: biblio-886689

RESUMEN

ABSTRACT This study aimed to evaluate the teratogenic and hepatotoxic potential of the usnic acid encapsulated into PLGA-microspheres. In total, 12 female Wistar rats in pregnancy were randomly distributed in the control group (n= 6) that received 1.0 mL of physiological solution and treatment group (n= 6) that received 25 mg/kg of encapsulated usnic acid by oral administration. All females were euthanized at day 20 of pregnancy and their fetuses were removed and analyzed. During the pregnancy was observed a reduction in weight gain. There was no difference in serum transaminases levels analyzed as well as any difference in liver weight in both groups. The histomorphometric analysis of the liver from the treatment group revealed an increase in number of hepatocytes and a decrease in nuclear area of these cells. Moreover, no alteration was observed in cell area of hepatocytes or number of Kupffer cells. The fetuses had an increase in total number of hepatocytes and a reduction in the amount of megakaryocytes. These results show the hepatotoxic potential of usnic acid during pregnancy. However, its toxicity can be minimized by encapsulation in microspheres.


Asunto(s)
Animales , Femenino , Embarazo , Ácido Poliglicólico/toxicidad , Ascomicetos/química , Benzofuranos/toxicidad , Ácido Láctico/toxicidad , Feto/efectos de los fármacos , Líquenes/química , Hígado/efectos de los fármacos , Ácido Poliglicólico/química , Valores de Referencia , Anomalías Inducidas por Medicamentos , Benzofuranos/química , Distribución Aleatoria , Ratas Wistar , Exposición Materna , Ácido Láctico/química , Peso Fetal/efectos de los fármacos , Hepatocitos/efectos de los fármacos , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Hígado/patología
18.
J Pharm Sci ; 106(8): 2106-2114, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28535975

RESUMEN

Paclitaxel (PTX) incorporation in poly(lactic-co-glycolic acid) (PLGA) matrices produce films with high tensile rigidity and slow release that fail to deliver the required release rate for most biomedical applications such as in drug eluting stents and cancer treatments. To modify and improve this behavior, a set of poly(diol sebacate)s were synthesized and fully characterized as possible additives. The tensile properties of PLGA blends were evaluated as these materials could be used as coatings in drug eluting stent applications. A significant improvement in mechanical flexibility was observed with 20% additive content, as it reduced the Young's modulus value and increased the maximum deformation at break. PTX release was studied and correlated with the release of additive from PLGA films. An increase in the initial burst release phase was observed on all blends when compared to the control films of PLGA. Modulation of PTX release was achieved by altering the hydrophilicity degree of the additive or its percentage content on the blend. This supports the possibility that PTX was partitioned into the additive phase. Cytotoxicity analyses of novel additives were performed on mouse embryonic fibroblasts NIH/3T3.


Asunto(s)
Antineoplásicos Fitogénicos/administración & dosificación , Materiales Biocompatibles/química , Ácidos Decanoicos/química , Ácidos Dicarboxílicos/química , Portadores de Fármacos/química , Ácido Láctico/química , Paclitaxel/administración & dosificación , Ácido Poliglicólico/química , Polímeros/química , Animales , Materiales Biocompatibles/toxicidad , Ácidos Decanoicos/toxicidad , Ácidos Dicarboxílicos/toxicidad , Portadores de Fármacos/toxicidad , Módulo de Elasticidad , Ácido Láctico/toxicidad , Ratones , Células 3T3 NIH , Ácido Poliglicólico/toxicidad , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Polímeros/toxicidad
19.
Drug Deliv ; 24(1): 40-50, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28155565

RESUMEN

Amphotericin B (AMB) is used most commonly in severe systemic life-threatening fungal infections. There is currently an unmet need for an efficacious (AMB) formulation amenable to oral administration with better bioavailability and lower nephrotoxicity. Novel PEGylated polylactic-polyglycolic acid copolymer (PLGA-PEG) nanoparticles (NPs) formulations of AMB were therefore studied for their ability to kill Candida albicans (C. albicans). The antifungal activity of AMB formulations was assessed in C. albicans. Its bioavalability was investigated in nine groups of rats (n = 6). Toxicity was examined by an in vitro blood hemolysis assay, and in vivo nephrotoxicity after single and multiple dosing for a week by blood urea nitrogen (BUN) and plasma creatinine (PCr) measurements. The MIC of AMB loaded to PLGA-PEG NPs against C. albicans was reduced two to threefold compared with free AMB. Novel oral AMB delivery loaded to PLGA-PEG NPs was markedly systemically available compared to Fungizone® in rats. The addition of 2% of GA to the AMB formulation significantly (p < 0.05) improved the bioavailability from 1.5 to 10.5% and the relative bioavailability was > 790% that of Fungizone®. The novel AMB formulations showed minimal toxicity and better efficacy compared to Fungizone®. No nephrotoxicity in rats was detected after a week of multiple dosing of AMB NPs based on BUN and PCr, which remained at normal levels. An oral delivery system of AMB-loaded to PLGA-PEG NPs with better efficacy and minimal toxicity was formulated. The addition of glycyrrhizic acid (GA) to AMB NPs formulation resulted in a significant oral absorption and improved bioavailability in rats.


Asunto(s)
Anfotericina B/administración & dosificación , Antifúngicos/administración & dosificación , Candida albicans/efectos de los fármacos , Portadores de Fármacos , Ácido Láctico/química , Nanopartículas , Polietilenglicoles/química , Ácido Poliglicólico/química , Administración Oral , Anfotericina B/química , Anfotericina B/farmacocinética , Anfotericina B/toxicidad , Animales , Antifúngicos/química , Antifúngicos/farmacocinética , Antifúngicos/toxicidad , Disponibilidad Biológica , Biomarcadores/sangre , Nitrógeno de la Urea Sanguínea , Candida albicans/crecimiento & desarrollo , Creatinina/sangre , Composición de Medicamentos , Ácido Glicirrínico/administración & dosificación , Ácido Glicirrínico/química , Hemólisis/efectos de los fármacos , Enfermedades Renales/sangre , Enfermedades Renales/inducido químicamente , Ácido Láctico/toxicidad , Pruebas de Sensibilidad Microbiana , Polietilenglicoles/toxicidad , Ácido Poliglicólico/toxicidad , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Ratas Sprague-Dawley , Tecnología Farmacéutica/métodos
20.
Microvasc Res ; 112: 14-19, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28161429

RESUMEN

Endothelial dysfunction is initial and critical step of atherosclerosis. Impaired bioavailability of endothelial nitric oxide synthase (eNOS) is one of the main reasons of endothelial dysfunction. Improving bioavailability of eNOS by increasing its expression or activity using statins is an effective therapeutic strategy in restoring endothelial dysfunction. In this study, simvastatin (SIM) as a poorly water-soluble drug was loaded in poly (lactic-co-glycolic acid) (PLGA) nanoparticles (SIM-PLGA-NPs). NPs were then conjugated with mZD7349 peptide (mZD7349-SIM-PLGA-NPs) and directed against vascular cell adhesion molecule 1 (VCAM-1). In vitro evaluation of the NPs for targeted delivery of SIM was performed on activated Human Umbilical Cord Vascular Endothelial Cells (HUVECs) by tumor necrosis factor alpha (TNF-α). Effect of mZD7349-SIM-PLGA-NPs and SIM-PLGA-NPs was compared on eNOS phosphorylation (ser-1177). Results of western blot showed SIM post-treatment increased significantly phosphor-eNOS (Ser1177) expression but no total eNOS expression. The study showed that mZD7349-SIM-PLGA-NPs have particle size, zeta potential value, polydispersity index (PDI) and encapsulation efficacy % of 233±18nm, -9.6±1.1mV, 0.59±0.066 and 69±17.3%, respectively. Also phosphor-eNOS (Ser1177) expression in activated HUVECs treated with mZD7349-SIM-PLGA-NPs was significantly (p<0.05) better than treated cells with SIM-PLGA-NPs. The results suggest that mZD7349-SIM-PLGA-NPs may be usable as an appropriate drug carrier for restoring endothelial dysfunction.


Asunto(s)
Antiinflamatorios/farmacología , Portadores de Fármacos , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Inflamación/prevención & control , Ácido Láctico/química , Nanopartículas , Péptidos Cíclicos/metabolismo , Ácido Poliglicólico/química , Simvastatina/farmacología , Molécula 1 de Adhesión Celular Vascular/metabolismo , Antiinflamatorios/química , Antiinflamatorios/metabolismo , Antiinflamatorios/toxicidad , Células Cultivadas , Composición de Medicamentos , Liberación de Fármacos , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Células Endoteliales de la Vena Umbilical Humana/patología , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/química , Inhibidores de Hidroximetilglutaril-CoA Reductasas/metabolismo , Inhibidores de Hidroximetilglutaril-CoA Reductasas/toxicidad , Inflamación/metabolismo , Inflamación/patología , Ácido Láctico/toxicidad , Óxido Nítrico Sintasa de Tipo III/metabolismo , Péptidos Cíclicos/química , Péptidos Cíclicos/toxicidad , Fosforilación , Ácido Poliglicólico/toxicidad , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Serina , Simvastatina/química , Simvastatina/metabolismo , Simvastatina/toxicidad , Solubilidad , Factores de Tiempo , Factor de Necrosis Tumoral alfa/farmacología
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